Wrays Solutions Pty Ltd v Zhejiang Zhuji United Chemicals Co., Ltd.

[2024] APO 44

IP AUSTRALIA

AUSTRALIAN PATENT OFFICE

Wrays Solutions Pty Ltd v Zhejiang Zhuji United Chemicals Co., Ltd.[2024] APO 44

Patent Application:                2019446196

Title:High-purity thermostable crystal form of substituted 3-isoxazolidinone compound, preparation method therefor, and application thereof

Patent Applicant:                   Zhejiang Zhuji United Chemicals Co., Ltd

Opponent:  Wrays Solutions Pty Ltd

Delegate:  Leslie F. McCaffery

Decision Date:  29 October 2024

Hearing Date:  29 July 2024, in Canberra.

Catchwords:  PATENTS – opposition under section 59 – polymorphs – construction – novelty – inventive step – utility – clarity – support – clear enough and complete enough disclosure – opposition successful on grounds of novelty, inventive step, clarity, clear enough and complete enough disclosure, support and utility – costs awarded – applicant given opportunity to amend.

Representation:  Counsel for the applicant:  David Larish

Patent attorney for the applicant:  Serena White and Charles Tansey of Spruson & Ferguson

Counsel for the opponent:  Melissa McGrath

Patent attorneys for the opponent: Daniel Beck, Craig Humphris and Bindhu Holavanahalli of Wrays

IP AUSTRALIA

AUSTRALIAN PATENT OFFICE

Patent Application:                2019446196

Title:High-purity thermostable crystal form of substituted 3-isoxazolidinone compound, preparation method therefor, and application thereof

Patent Applicant:                   Zhejiang Zhuji United Chemicals Co., Ltd

Date of Decision:                   29 October 2024

DECISION

The opposition is successful.

Claims 1, 2 and 9 lack novelty.  Claims 1, 2, 9 and 10 lack an inventive step.  Claim 2 lacks clarity.  Claim 3 lacks utility.  Claims 3 to 7 lack support.  The specification does not provide a clear enough and complete enough disclosure of the invention defined in claims 3 to 7.

The opposition is unsuccessful in respect to claim 11.

The applicant stated that they do not press claim 8.  No determination has been made on this claim on the assumption that it will be deleted.

The applicant has 2 months from the date of this decision to propose amendments to overcome the issues identified above.  These amendments should include deletion of claim 8.

Costs according to Schedule 8 are awarded against the applicant, Zhejiang Zhuji United Chemicals Co., Ltd.

REASONS FOR DECISION

Background

1.Application 2019446196 was filed on 13 May 2019 under the provisions of the Patent Cooperation Treaty by Zhejiang Zhuji United Chemicals Co., Ltd. (the applicant).  It was advertised as accepted on 9 February 2023.  A notice of opposition was filed by Wrays Solutions Pty Ltd (the opponent) on 8 May 2023.

2.A statement of grounds and particulars (SGP) was filed on 8 August 2023.  The grounds of novelty, inventive step, usefulness, clear enough and complete enough disclosure, clarity and support were raised in the SGP. 

3.Evidence in support was completed on 6 November 2023, and comprised a declaration by Stuart R. Batten (Batten), together with Annexures SRB1-1 to SRB1-8. 

4.No evidence in answer was filed by the applicant, and accordingly no evidence in reply was required.  The matter was set for hearing on 29 July 2024.  The opponent provided a summary of submissions (OS) for the hearing on 15 July 2024, pressing the grounds of novelty and inventive step (claims 1, 2 and 9 to 11), clarity (claims 2 and 8), clear enough and complete enough disclosure (claims 2 to 11), support (claims 3 to 8), and utility (claims 3 to 8).  The applicant filed their summary of submissions (AS) for the hearing on 22 July 2024.  The applicant stated that they are not pressing claim 8.  That is, I understand that they intend to amend to delete this claim.  I have proceeded on that understanding and therefore have made no determination in relation to that claim.

Onus

1.The substantive amendments to the Patents Act 1990 (Cth) (the Act) brought about by the Intellectual Property Laws Amendment (Raising the Bar) Act 2012 (Cth) (the RTB Act) apply to the present case.  The standard of proof in opposition proceedings is the balance of probabilities.  If the Commissioner is satisfied, on the balance of probabilities, that a ground of opposition to the grant of the standard patent exists, the Commissioner may refuse the application.  The opponent bears the onus of proof.

Principles of construction

1.The principles underpinning construction are well-established.  As noted by Middleton J in Eli Lilly and Company Limited v Apotex Pty Ltd:

“It is well settled that the Court should, from the outset, approach the task of patent construction with a generous measure of common sense. The Court must place itself in the position of a person skilled in the relevant art, being the subject matter of the patent. From this perspective, the patent is to be read as a whole, in the context of the specification and in light of the prevailing common general knowledge and state of the relevant art at the priority date.”

1.Thus, the task of construing the specification is undertaken from the viewpoint of a person skilled in the art and the prevailing common general knowledge at the priority date.  The person skilled in the art is a hypothetical non-inventive person or team likely to have a practical interest in the subject matter of the invention. 

2.The Full Court in Airco Fasteners Pty Ltd v Illinois Tool Works Inc., recently reiterated the principle that experts can give evidence on the meaning which those skilled in the art would give to technical or scientific terms and phrases and on any unusual or special meanings that would be given by skilled addressees to words which might otherwise bear their ordinary meaning.  The Court is to place itself in the position of some person acquainted with the surrounding circumstances as to the state of the art and manufacture at the time.  However, it is for the Court, not for any witness however expert, to construe the specification.  A similar approach is taken in matters before the Commissioner. 

The person skilled in the art

1.As indicated above, the only evidence in the present matter is from Professor Batten from  the School of Chemistry at Monash University.  He stated that he had been active in the field of crystallography since 1990.  He has extensive experience in powder X-ray diffraction (PXRD, otherwise known as X-ray powder diffraction or XRPD) techniques.  He also stated that he developed a substantial knowledge of polymorphs of small molecules, including pharmaceutical compounds.  While this experience may not be specific to agricultural chemicals, I do not understand the underlying principles to differ in any significant way.

2.The present invention relates to an allegedly new crystalline form, or polymorph, of an existing herbicide, bixlozone.  The applicant submitted that the skilled person would therefore comprise a team having skills and experience in the preparation, evaluation and use of agrochemical formulations, chemical synthesis and crystallography.  I consider this a reasonable representation of the skilled person. 

3.The opponent did not specifically identify the specific skills of the skilled person, but submitted that the team “at least includes a scientist in the field of chemistry, particularly with a background in identifying, isolating and characterising polymorphs, with a sound knowledge of X-ray diffraction techniques, as well as methods of making crystals such as various recrystallisation methods”.  There is no dispute that Professor Batten possesses these skills, though the applicant noted that no evidence had been provided by a person with skills and knowledge in the use and formulation of agrochemicals.  I have dealt with this particular issue as necessary in my determination.

The common general knowledge (polymorphs)

1.Crystals are solids that are made up of atoms, molecules and/or ions arranged in a repeating formation.  Non-crystalline solids which do not have a repeating pattern at the molecular level are amorphous.  Organic and inorganic compounds can exist in both crystalline and amorphous forms.  Some materials can exist in multiple crystalline forms or polymorphs.  Molecules of water, solvent or other impurities can also be incorporated into the crystal structure, resulting in hydrates and solvates referred to as “pseudo-polymorphs” because they are not true polymorphs. 

2.Not all crystalline compounds exist in different polymorphic forms, but as Professor Batten stated:

“In my experience, and based on my reading, only one crystalline form has been discovered for most compounds, because polymorphism generally tends to be only investigated in a particular compound when the compound becomes a commercially important one. However, it is not uncommon for polymorphs to be found when a compound is investigated in detail.  As stated by W.C. McCrone in what has become a famous quote in this field (in Phys. Chem. Org. Solid State, 2, 1965, pages 725-767); "It is at least this author's opinion that every compound has different polymorphic forms and that, in general, the number of forms known for a given compound is proportional to the time and money spent in research on that compound". Since pharmaceutical compounds are the subject of intensive investigation, many of the known examples of polymorphism are small organic molecules of pharmaceutical compounds.”

1.Different polymorphs generally have different physical properties.  The existence of a  polymorph and its physical properties can’t be predicted and instead need to be determined experimentally.  This generally involves re-crystallization of the material, a widely used technique that involves dissolving the material in a solvent and lowering the solubility of the substance so that it reaches saturation point and crystallizes (or precipitates) out of the solution.  Crystallization can be facilitated by lowering the temperature of the solution, adding another solvent in which the material is less soluble, changing the pH of the solution, or increasing the concentration of the material by evaporating the solvent.  Crystallization can also be induced by providing a surface for nucleation (for example, by scratching the side of the flask), or by adding a seed crystal (a previously made crystal of the desired polymorph).  Seeding is one of the methods used in the present invention.

2.Recrystallisation using different solvents can sometimes give different polymorphs.  Generally an amorphous solid will be obtained when a substance rapidly precipitates from the solution as there is insufficient time for crystals to form.  It is also possible for one polymorph to change to another polymorph over time.  Polymorphs may be “kinetically” or “thermodynamically” stable.  The thermodynamically stable (or thermostable) polymorph is the most stable, or lowest energy form (or phase).  In theory, any system will move over time to the most stable phase.  However, the transition from one phase to another requires a certain amount of energy, known as the activation energy.  If there is insufficient energy to overcome the activation energy, the system becomes trapped in a less stable phase, known as a kinetically stable or metastable phase.  A kinetically stable phase can be formed more quickly as it is easier for the molecules to assemble in this arrangement.

3.Once a kinetically stable phase has been formed, it can convert into the more thermostable form if sufficient energy is put into the system to overcome the activation barrier.  This can occur if the material is heated, or during certain treatments such as grinding.  Conversion can also occur spontaneously, without the addition of further energy, though the rate at which this occurs  varies widely between different materials.  Polymorph studies are therefore important in the development of new chemical entities as the different physical properties can have implications for the handling, formulation and pharmacokinetics of the material. 

The specification and claims

1.The invention is said to relate to a high-purity thermostable crystal form of 2-(2,4-dichlorophenyl)methyl-4,4-dimethyl-3-isoxazolidinone (I). 

1.Compound I is a herbicide known commercially as bixlozone.  It has apparently garnered increased interest in recent years due to its low volatility compared with the widely-used isoxazolidine herbicide clomazone.  Clomazone differs from bixlozone in the absence of the para-chloro group in the phenyl ring.

2.The specification refers to various prior art disclosures of the preparation and use of bixlozone in herbicidal formulations.  Bixlozone has been obtained as an oily substance, which is said to have been used for the preparation of suspension concentrates (SC).  These comprise the solid active ingredient dispersed in a liquid carrier.  The specification states that the preparation of SC from oily materials requires adsorption of the substance on to a solid carrier such as white carbon black, mixing with a master powder and mechanical pulverisation of the master powder.  These additives add to the cost of formulation, and pose safety and environmental hazards because of the dust generated during processing.  The specification also refers to water dispersible granules (WG), solid formulations which dissolve to provide a dispersion of the solid active ingredient when added to water.  Emulsion concentrates (EC) are another typical formulation, comprising a water in oil emulsion of the active ingredient dissolved in an organic solvent.

3.Bixlozone has also been obtained as a monoclinic crystal with a melting point of 45°C.  This is said to be unsuitable for preparation of “green and environmentally friendly agrochemical formulations”, including SC.  These apparently require the active ingredient to have a melting point of greater than 60°C and solubility in water of less than 100 mg/L.  Lower melting points can lead to melting and softening during the pulverisation and grinding processes.  This  affects the physical stability of the SC, resulting in flocculation and paste formation.  The specification suggests that SC formulations comprising lower melting point materials are also prone to delamination and particle size enlargement during storage.

4.The specification states that bixlozone has not been reported as a WG, nor as a pre-emergent herbicide for weed control in wheat.  The specification goes on to say that:

“To address the shortcomings of the present technology, the inventors discovered a more thermostable crystal of the 2-[(2,4-dichlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone compound (Formula I) through enormous amount of experimental design and laboratory validation.  The inventors also discovered this high-purity thermostable crystal can be more conveniently and efficiently used to prepare green and environmentally friendly agrochemical formulations, such as suspension concentrate (SC) or water dispersible granule (WG).”

1.The first aspect of the invention, which is also defined by Claim 1, relates to a crystal of bixlozone characterized in that the crystal is an orthorhombic crystal, with a space group of P21 21 21 and 30 lattice parameters of a=9.2301 (2) Å, b=11.0751 (3) Å, c=12.7554 (3) Å, α=90°, β=90°, and γ=90°; and a melting point of the crystal ranges from 83°C to 85°C.

2.Crystalline substances have a unique unit cells, which produce unique PXRD patterns that can be used to distinguish one crystal form from another.  My understanding is that the space group and lattice parameters defined in Claim 1 relate to the dimensions of the unit cell of the polymorph.  The specification also provides a PXRD spectrum for the polymorph and identifies eight of the strongest PXRD parameters.  Claim 2 recites these parameters, but only requires that the diffraction pattern include at least 3 of these parameters.  The opponent made submissions on this point under the ground of sufficiency, which I have dealt with later.  The term “orthorhombic” is also used in the claim, but the unit cell dimensions indicate that the crystal has that particular form, so the inclusion of this term in the claim probably serves no additional purpose over the defined lattice parameters.  Orthorhombic crystals generally present as a blocky crystals but, as is the case here, may be acicular (needle-shaped).

3.One of the main disputes between the parties that impacts on several grounds of opposition, relates to the defined melting point temperature range.  The opponent submitted that measured melting points can depend on variables such as the apparatus used to determine melting point, different ramp rates or methods,  but none of the conditions used to measure the melting point are provided.  Solids generally melt over a small temperature range rather than a single temperature point, and the opponent noted the present polymorph melted over a range of temperatures between 80°C to 85°C when measured by DSC.  They concluded, based on these observations, that differences in the realm of 1°C fall well within experimental margins of error of DSC.  The skilled person therefore would not understand the defined temperature range of 83°C to 85°C to be a hard and fast cut-off.

4.The applicant argued the opponent’s construction is motivated by an attempt to shoehorn the disclosure in the prior art into the claim. They submitted that the application indicates that precision is important: specific temperatures are used throughout the specification, lattice parameters are given to four decimal places, and the herbicidal doses are given to up to three decimal places.  Where a degree of variability is permitted in the application, this is made clear in the claim or specification (for example, the variability given in the XPRD parameters of ±0.2).  The applicant argued that the claimed range is based on the measurement of 83.8°C, the 83°C to 85°C range already factors in a margin for experimental error.  However they submitted that, if contrary to the above, the claimed range is broadened, “such broadening should involve no more than rounding to the nearest whole number”, which they considered would be 82.50°C to 85.49°C. 

5.I do not entirely agree with the applicant’s submissions on this point.  For example, the applicant suggested that the range has been selected around the melting point of the seed crystal isolated in Embodiment 3, but my understanding is that the range is simply a generalisation of the specific melting points of the products prepared in Embodiments 4 (m.p. 84.5°C), 5 (m.p. 83°C), and 6 (m.p. 83.5°C).  I also note that, contrary to the applicant’s submission that the range factors in any experimental error, the lower limit is set at the precise temperature of the product obtained in Embodiment 5.  That is, there is no experimental error factored into the lower end of the range based on this example.  Furthermore, it isn’t entirely clear how the applicant’s suggested “broadened” range of 82.50°C to 85.49°C has been determined by rounding to the nearest whole value.  If it is intended to allow variability of 1°C from the highest (embodiment 4) and lowest (embodiment 5) measured values, then the range would be 82°C to 85.5°C.  Ultimately, while the defined range may be based in some way around the experimental results, the specific upper and lower limits of the range are essentially arbitrary.

6.However, I agree with the applicant to the extent that the construction of terms should be undertaken without regard to the alleged infringing articles, better understood for present purposes as the prior art.  It is also well-established law that claims should be given a purposive construction, and the terms used in a claim should be given the meaning that the skilled person would give them.   In the present case, I understand Professor Batten interpreted the claimed invention as being directed towards a specific crystal form, or polymorph, per se.  The crystal has various intrinsic or inherent properties and, as is the case here, these can be used to identify (or characterise) the new polymorph and distinguish it from other crystal forms of the same compound.  These features are essential inasmuch as the polymorph will exhibit them, if measured.  It follows that if two polymorphs are the same then simply articulating further intrinsic or inherent properties will not serve to distinguish the two forms.  There may also be other properties that are not inherent, such as particle size or hygroscopicity, that might distinguish two different physical forms of the same polymorph.  But I do not understand this to be a relevant consideration in the present case.

7.The dispute between the parties essentially lies in how the person skilled in the art would view the defined temperatures as opposed to the extent to which differences in temperature can be relied upon when comparing two different polymorphs.  Looking at the terminology used in the claim, and in isolation from the prior art, the temperature range defined in claim 1 would be understood as being 83°C to 85°C.  There is no qualification or imprecision imposed on the defined range, either explicitly in the claim or implicitly through any definition given in the specification or purposive reading by the skilled person.  The opponent’s concerns relate more to whether, given two different crystals that have similar melting points, a comparison of the specific characteristics of each establish that they are different crystal forms as asserted by the applicant.  That is a distinct and separate consideration under other grounds, including novelty, which is discussed in greater detail under those grounds.

8.The invention is said to include a method for preparing a stable seed crystal of bixlozone, which can be used to induce crystallisation of the specific polymorph from solutions.  The seed crystals are prepared by the steps of dissolving the prior art monoclinic crystal of bixlozone in a solvent, slowly volatilizing the solvent through heating, cooling and re-heating, and then crystallizing to obtain the orthorhombic seed crystal.  The solvent is selected from alkanes and cycloalkanes.  The weight ratio of bixlozone to solvent is in the range of 1:10-20.  The mixture is first heated to 40 to 90°C, cooled to -10 to 10°C for 10 to 20 hours, and re-heated to 15 to 40°C.  The volatilization process lasts for 3 to 30 days.  This process appears to simply involve allowing the solution to evaporate at room temperature over an extended period of time. 

9.Embodiment 3 describes a specific example of this process.  The monoclinic crystal is dissolved with heating in petroleum ether and then cooled to 0°C for 18 hours.  The mixture is then kept at room temperature for 20 days (which I understand to comprise the “re-heating” step), slowly volatilized and crystallized.  The process results in a mixture of acicular crystals deposited on the surface of rhombohedral crystals.  The acicular crystals are separated to provide the seed crystals of the invention.  The seed crystals are used in a method of “efficiently” preparing the orthorhombic crystal of bixlozone.  The process essentially involves dissolving crude bixlozone in a solvent and, while cooling, adding a seed crystal of the orthorhombic polymorph.  This aspect of the invention is reflected by Claims 5 to 7. 

10.The specification then sets out several embodiments describing the preparation of prior art materials and the crystal form of the present invention, stability studies on the crystals, as well as their use in the preparation of different agrochemical formulations.  Formulations comprising the polymorphs of the invention are said to show high levels of pre-emergent herbicidal activity in comparison to a commercial product, Command™, against Stellaria media and Poa annua L., which is said to show that the formulations are safe in crops such as corn and wheat. 

11.These embodiments are reflected in Claims 9 to 11.  Claims 9 to 11 are not limited to any particular mode of application, and I therefore understand them to include both pre-emergent and post-emergent application.  The opponent also noted that claim 9 defines “an application” of the crystal of the invention “in the preparation of agricultural formulations and control of unwanted weeds”.  They read the latter features as being separate applications – that is, the agricultural formulations are not necessarily used in the control of weeds.  The crystal form of the invention may also be used directly for the control of unwanted weeds.  They went on to further note that the crystal form may not be maintained in an agricultural formulation.  For example, if the formulation is a solution of the crystalline form, then the crystal form itself will no longer be present. 

12.Contrary to these submissions, I understand the claim as defining a method (“an application”) comprising both steps of formulating and using the crystal form of the invention.  That is not to say that the crystal cannot be used “directly” as a herbicide, though it would seem to me that some kind of formulation or treatment would be required in order for the crystalline material to be suitable for such use.  I also agree that the claim includes formulations that do not retain bixlozone in the crystalline form of the invention, but do not consider that an issue.  The final product may not comprise the crystalline form, but the process of making it would be understood as using the crystal form of the invention. 

13.Claim 10 limits the application to formulation as a WG or SC, the crop species to wheat, rice, sorghum, barley or rye, and the unwanted weeds to comprise a list of weed species.  The specification states that weeds in a corn mays (sic) field mainly comprise the first 31 species defined in claim 10, weeds in a wheat field mainly comprise another 31 species named in claim 10, and that “other” weeds include the last 33 species listed in claim 10. 

14.Claim 11 limits the application to formulation of the crystal form as a water-dispersible granule, the crop species to corn and wheat, and the weed species to Stellaria media and Poa annua L.  A literal interpretation of the claim might suggest that the claim is limited to treatment of only the two weed species in the crop species.  Clearly this would not be feasible in a crop containing a variety of different weed species.  A common-sense interpretation would be that the two weed species are at least present, in addition to other weed species.

Novelty

1.An invention is taken to be novel when compared with the prior art base unless it is not novel in light of certain types of prior art information, each of which must be considered separately. 

2.It is well-established that the general test for anticipation is the reverse infringement test:

“The basic test for anticipation or want of novelty is the same as that for infringement and generally one can properly ask oneself whether the alleged anticipation would, if the patent were valid, constitute an infringement.”

1.Thus, the test is satisfied if the alleged anticipation discloses all of the essential features of the invention as claimed.  Furthermore, as stated by the Full Court in AstraZeneca v Apotex:

“… for a prior art document to be anticipatory, there must be … a clear description of, or clear instructions to do or make, something that would infringe the patentee’s claim if carried out after the grant of the patentee’s patent.”

1.A classic formulation of this principle was given in General Tire v Firestone, which stated that the prior art “must contain clear and unmistakable directions to do what the patentee claims to have invented… a signpost, however clear, upon the road to the patentee’s invention will not suffice.  The prior inventor must be clearly shown to have planted his flag at the precise destination before the patentee.” 

2.At the hearing the opponent pressed the ground of novelty against Claims 1, 2 and 9 to 11 with respect to WO 2019030177 (D1), or alternatively, in light of the combination of D1 and US 4405357 (D2).  The opponent considered D1 provides the necessary novelty destroying disclosure, but also uses a method for the preparation of bixlozone that was disclosed in D2.  The opponent submitted that the disclosures of D1 and D2 could therefore be considered a single source of information for the purposes of novelty as D1 explicitly refers to and relies on the disclosure of D2.  The applicant did not dispute this submission.  To the extent that it is necessary, I accept that D1 and D2 may be read as a single source of information, but only to the extent that it relates to the cross-referenced preparation of bixlozone.  I do not consider that the two separate documents would be read as a single source of information for other matters such as the formulation and use, though the combination of information may well be relevant in the inventive step determination.

3.D1 discloses a crystal form of bixlozone which is designated as crystal form A (form A).  Bixlozone is said to crystallize in three forms: form A which has a melting point of 82°C, form B which has a melting point of 72°C, and form C which has a melting point of 44°C.  Form A is suggested to be the thermodynamically stable form.  The gist of the opponent’s submissions is that claims 1, 2 and 9 to 11 include features that are inherent to form A, and/or include features that are arbitrary parameters (such as melting point and peak intensity), which do not confer novelty on the claimed invention.  They relied on the evidence of Professor Batten that:

·PXRD analysis provides a “definitive fingerprint” for a a particular crystalline form of a solid material;

·A comparison of the diffraction pattern of form A given in D1 with the diffraction pattern set out in Table 2 of the present application reveals peaks at each of the 8 key positions set out in that table;

·There are differences in the relative intensities of the peaks, and there are additional peaks present in the diffraction pattern in D1, but this is insufficient to conclude that they are different crystal forms;

·The melting points given in D1 and the present application are different but due to the different methodologies used to determine melting point, a difference of 1.8°C is well within the normal margin of error.  This is not indicative of the crystal forms being different to each other.

·Taken together, on a comparison of the melting point data and the PXRD, form A disclosed in D1 is the same crystalline form as the orthorhombic crystal defined in the present application.

1.The applicant’s submissions in response went to three issues, which they consider failed to establish that D1 anticipated claim 1:

·The evidence does not establish that D1 provides an enabling disclosure;

·D1 does not disclose a melting point of the crystal in the range of 83°C to 85°C.  The evidence does not establish as a hard fact that form A inevitably has a melting point in the range of 83°C to 85°C.

·The evidence does not establish as a matter of hard fact that Form A satisfies the space group and lattice parameters defined in Claim 1.

1.The applicant argued that there is no planting of the flag in the claimed range, and the fact that the melting point of Form A is close does not suffice.  The inconsistencies associated with different measurement conditions, and the assertion that melting points can vary by between 1°C and 5°C do not assist the opponent since D1 is silent as to how the melting point of Form A was determined, and based on the opponent’s assertion the melting point of Form A could be substantially lower than 82°C, or even greater than 85°C.  They considered this makes it even harder to establish that the inevitable result of following the directions in D1 would give a crystal within the range defined in the present claims, noting Professor Batten’s evidence that the properties of a polymorph generally need to be determined experimentally.

2.The applicant also submitted that Professor Batten was asked from the outset to compare D1 “to determine whether, based on my knowledge of polymorphs, the Bayer Application disclosed” the same or different crystalline form to the orthorhombic crystalline form of the present application.  They submitted that evidence as to novelty should avoid identifying in hindsight what is disclosed in the prior art.  They considered the instructions were an invitation to engage in hindsight-based reasoning, citing the guidance provided in Fieldturf Tarkett Inc v Tigerturf International Ltd:

“Hindsight is just as “insidious” in a novelty context as with obviousness because the invention cannot have “been before made known” if one uses (even subconsciously) one’s knowledge of the invention as claimed in the patent in suit to identify the relevant features in the prior art.”

1.I agree that hindsight should be avoided when determining whether there has been a disclosure of the invention by the prior art, particularly where, as was the case in Fieldturf Tarkett Inc v Tigerturf International Ltd, the invention consists of a combination of integers.  The risk in such cases is that the features of the combination are read out of a disclosure despite there being no “teaching” of the specific combination.  In the present case, the invention relates to a polymorph or crystal form which is characterised by certain intrinsic features of the material.  D1 discloses a polymorph of bixlozone.  Professor Batten’s evidence and the conclusions he draws are largely based on an objective comparison of the physical and crystallographic data disclosed in each document.  I do not have any significant concerns in relation to the instructions that Professor Batten was given and the evidence that he has provided in this matter.

2.On balance, I am satisfied that the crystal form disclosed in D1 is the same crystal form as that claimed in the present application.  In short, while there may be some differences in the features of the claims, these are either inherent or of a nature that does not distinguish the present invention and form A as disclosed in D1as two different polymorphs. 

3.The claimed invention is a specific polymorph which is identified by particular properties of the polymorph.  There is no dispute that the crystal lattice and crystal form parameters are not disclosed in D1.  However, that in itself does not establish that the crystal forms are different.  These are simply particular parameters that the applicant has chosen to characterise the crystal form of the invention and to attempt to distinguish it from prior art crystal forms. 

4.On the other hand, both D1 and the present application provide melting points and PXRD data that may be directly compared.  To that end, Professor Batten noted that the present application gives a melting point for the thermostable form of 83.8°C using DSC, but the DSC trace shows that the crystal melts over a range of temperatures commencing at about 80°C continuously through to about 85°C, under ramp rate conditions of 10°C/min.  Professor Batten went on to state that:

“Meanwhile, crystalline form A in the Bayer Application is reported as having a melting point of 82°C. The method for determining the melting point is not disclosed in the Bayer Application, and even if DSC was used to measure it, we do not know the ramp rate that was employed. As such it is not possible, in my opinion, to say that the apparent difference in melting points of 1.8°C between the crystalline form A of the Bayer Application (82°C) and the orthorhombic crystalline form of the Opposed Specification (83.8°C) sufficiently characterize the two reported crystalline forms as being different crystalline forms.”

1.Professor Batten considered that the difference was well within experimental error, especially where two melting points are determined on different apparatus, potentially at different ramp rates, or potentially by completely different methods.  He also observed that form A was not purified by recrystallization, and therefore he expected that there would be some impurities present in the sample.  Even small amounts of impurities can lower the melting point of a crystalline substance by between 1°C and 5°C.  As a consequence, Professor Batten considered that, based on melting point alone, he could not say that form A in D1 is any different to the present crystal form. 

2.PXRD is considered in the art to be akin to a fingerprint that can be used to distinguish between polymorphs.  Professor Batten considered that a comparison of the PXRD data would be needed to be certain that the two crystal forms are different.   The PXRD spectrum given in D1 provides twenty 2Ɵ reflexes.  The eight key values given in the present application have corresponding values in D1:

1.Professor Batten acknowledged that form A of D1 contains additional peaks not shown in Figure 6 of the present application.  However, he stated that this may be consistent with the presence of impurities as would be expected from the lack of purification performed in D1.  It is also likely to be due to the higher resolution, better signal-to-noise and reduced preferred orientation effects of the PXRD pattern given in D1. 

2.To the extent that the PXRD peak at 10.529° is the most intense for the present crystal form, Professor Batten stated that he focussed on the location (that is, the 2Ɵ values) of the most intense peaks in the PXRD spectrum rather than their relative intensities.   He referred to the standard text, “Polymorphism in Pharmaceutical Solids” which states that “it has been noted that relative intensities may vary considerably from that of the reference standard, making it impossible to enforce a criterion based on the relative intensities of corresponding scattering peaks.”  The relative intensity of peaks is also susceptible to preferred orientation effects that can be affected by the degree of grinding during sample preparation, and is particularly pronounced in crystals having a geometry where the length of the crystal is much greater than the width and/or height of the crystals, as is the case with acicular crystals.  Professor Batten did not consider that “even major variations in the intensities of peaks in two samples are a good indication that the two samples are different polymorphs”.  He concluded that, on a comparison of the melting point and the PXRD data, taken together, it was his opinion that the crystal form disclosed in D1 is the same as the one defined by the present claims.

3.I am satisfied that Professor Batten’s evidence clearly establishes that Form A disclosed in D1 is the same polymorph as the present invention.  The evidence also indicates that PXRD parameters are intrinsically linked to the crystal structure (that is, the lattice parameters), and therefore also to the orthorhombic crystal form.  It follows that these features of the claim are inherent in the polymorph disclosed in D1. 

4.That brings me back to the issue of form A disclosed in D1 having a melting point that falls outside the range claimed in the present application.  The present claims are directed to the crystal form per se – that is, the claims define a specific crystal form characterised by several physical properties.  While there are different physical properties that could potentially be used to characterise a crystal form, some of these may be less reliable when it comes to distinguishing between two crystal forms.  The applicant’s submissions that the present invention is a different crystal form are largely to the point that melting point should be preferred to PXRD which is a gold standard for characterising and distinguishing polymorphs.  Similarly, the intensity of a single peak is relied on in preference to the positions of numerous PXRD peaks, including all of the major peaks identified in the present specification.  Notably, the applicant provided no evidence in support of these assertions.

5.The evidence before me indicates that melting point is generally used as a starting point for characterising a polymorph as it is a relatively quick and simple means of distinguishing one polymorph from another.  The evidence clearly establishes that different polymorphs can, in rare cases, have similar melting points, and therefore melting point is a less definitive means of distinguishing polymorphs in such situations.  Melting points can also be affected by the conditions used when taking the measurement, and by impurities in the sample that can result in variations of up to a degree or two.  In the present case, the melting point of several of the present embodiments and the polymorph disclosed in D1 is well within this range of error.

6.I accept that two different polymorphs of the same material could have similar melting points, but the suggestion that two different polymorphs could have almost identical PXRD (in this case 21 out of 22 identified PXRD peaks) would not seem plausible based on the evidence before me.  Indeed, the present invention is based on several different experiments that provide products having different melting points across a range of about 1.5°C.  PXRD in each case confirms that they are the same crystal form.  The applicant’s submission that the polymorph could have such a high level of similarity in its PXRD yet be a different polymorph based on its melting point is not consistent with the data derived from their own experiments. 

7.But even setting the issue of experimental error and impurities aside, it would seem to me that melting point is an intrinsic property of a solid material.  That being the case, the polymorph disclosed in D1 would inherently possess the claimed melting points, noting that the present specification suggests that the crystal form melts across a range, rather than at a single melting point. 

8.In coming to this conclusion I acknowledge that the embodiments show that bixlozone crystallizes from different solvents with different melting points.  There could be an argument that this results in different crystalline structures (such as different solvates) and a range of melting points for the different crystals, rather than a single specific melting point.  However there is nothing in the specification that would establish this to be the case, and all testing and discussion of the invention relates to a single crystal form.  There is otherwise no other suggestion in the specification that the invention lies in a different form(s) of a known polymorph.  In any case, at the hearing the applicant did not resile from their position that this is a new and different polymorph to that disclosed in D1 based on the different melting point. 

9.I therefore consider that D1 discloses the crystal form of present claims 1 and 2.

10.But it isn’t enough that the prior art simply discloses the invention – it must also enable the invention.  A key issue in that respect is whether, following the instructions given in D1, a crystal according to the present claims would inevitably be obtained.  To that end, the applicant submitted that the prior art must disclose an invention which, if performed, would necessarily infringe, or as stated in H Lundbeck A/S v Alphapharm Pty Ltd, if following the prior art disclosure of a method that is said to produce the claimed product “may or may not result in the claimed product, there is no anticipation”. 

11.In my opinion, the issue here is not whether the directions given in D1 are capable of being carried out in a manner which would infringe the patent, but also as likely in a manner which would not do so.  There is no dispute between the parties that D1 uses the method disclosed in D2.  There is also no suggestion that the directions given in D1 (or D2 for that matter) could be carried out in different ways – that is, bixlozone is prepared by the method described in D2.  The difference between the parties is whether following the process of D1 inevitably provides a crystalline product. 

12.The applicant argued that Example 22 of D2 obtains bixlozone as an oil and that D1 does not disclose how any crystalline material is obtained from that oil.  On the other hand, the opponent noted that D1 explicitly states that Form A was made according to the method set out in D2, and noted the statement in D1 that:

“The crystal form of 2-(2,4-dichlorophenyl)methyl-4,4-dimethyl-3-isoxazolidin-3-one which is present after preparation without any further crystallization/recrystallization steps has been characterized for the first time and is referred to hereinafter as crystal form A or modification A.”

1.Professor Batten understood this to mean that “the oil produced by the method as stated in US 4,405,357 spontaneously crystallizes ‘after preparation’ – in other words, either during or after the final step described in that document”.  The applicant took issue with Professor Batten’s reference to the oil spontaneously crystallizes, arguing that there was no explicit disclosure in D1 of “spontaneous crystallization”, and that his evidence on this point was formed in hindsight after reading the present application.  I agree that D1 does not use the specific term, but I understand the term “spontaneous” simply means that something occurs without any external causes.  The reference in D1 to the crystal form of bixlozone being present after preparation without any further crystallization steps would seem to me to be consistent with that meaning.

2.The present specification also purports to repeat the method of D2 in Embodiment 1, but in contrast to the result in D1, an oily substance is obtained.  This might suggest that the method described in D2 does not enable the preparation of form A, or at best does not provide it consistently.  However, Professor Batten considered that the different result may be because the method used in the present application is not a “faithful repeat” of the method described in D2.  In particular, Professor batten referred to the final three steps in the process of D2 as shown below:

1.Professor Batten noted that at several points in the synthesis described in Embodiment 1 of the present application, reaction products have not been “rigorously” purified in accordance with the protocols given in D2.  In particular:

·Step 1 of Embodiment 1 omits a potassium hydroxide treatment and extraction with dichloromethane, and does not describe the purification of the hydroxylamine product by recrystallization.

·Step 2 omits a brine wash, a hexane suspension (slurrying) step, and does not describe the purification of the propionamide by recrystallisation.

1.Professor Batten considered the latter was a particularly serious omission since the propionamide is the final intermediate before cyclisation to form bixlozone.  He considered that significant impurities would be present in the product of the present application compared to the product of D2.  Professor Batten also noted that a further difference is that steps 1 and 2 are carried out on a larger scale (2- and 3.5-fold greater respectively), and this may have led to increases in the amount of impurities in the product. 

2.At the hearing the opponent suggested that these differences had been “designed to fail”.  I have no reason to conclude that is the case, but I consider it plausible that an accumulation of impurities would impact on the crystallization of the final product.  D2 states that an oil is obtained, but it would seem to me that this was simply what was observed at a point in time in a particular experiment in an early stage of compound synthesis and screening as opposed to a focussed study of the properties of a specific known compound.  While the applicant argued that D1 does not disclose how any crystalline material is obtained from the oil of D2, much less a crystal having a particular crystalline form, D1 states that a crystal is obtained using the same method of preparation, and characterises that product in some detail.  There is no evidence that would lead me to determine that this is not the case. 

3.As an aside, my conclusion is arguably consistent with the contemporaneous prior art discussed in the present specification.  D1 states that for the first time, the crystal which is present after preparation of bixlozone (using the method of D2) has been characterised.  This suggests to me that there may have been other occasions on which a crystalline material has been obtained but not characterised.  For example, D3 uses “powdered” bixlozone, which is said to be made by the method of D2.  The present specification notes that details of the pulverisation process are not provided in D3 but the suggestion is that bixlozone is adsorbed onto a solid carrier.  However, in my opinion there is no indication in D3 that a solid carrier is used.  On an ordinary reading of D3, I take the disclosure to be that the solid material comprises only bixlozone.  I note that this is not a factor in my conclusion, but it does appear to support the suggestion that bixlozone had previously been found to crystallize. 

4.In summary, I am satisfied that the crystal form defined by Claims 1 and 2 lacks novelty in view of D1 in that it is both disclosed and enabled.  D1 also discloses the use of Form A in the preparation of agrochemical formulations, and as herbicides.  Claim 9 therefore also lacks novelty in view of D1.

5.Claims 10 and 11 define more specific methods of preparing and using agricultural formulations.  The formulations are limited to water-dispersible granules and suspension concentrates, and the use to particular crops and weed species.  D1 does not disclose any specific formulations of these types and their use as herbicides, but states that:

“Compound of formula (I) and/or salts thereof can be formulated in various ways according to which biological and/or physicochemical parameters are required. Possible formulations include, for example: wettable powders (WP), water-soluble powders (SP), water-soluble concentrates, emulsifiable concentrates (EC), emulsions (EW), such as oil-in-water and water-in-oil emulsions, sprayable solutions, suspension concentrates (SC), oil- or water-based dispersions, oil-miscible solutions, capsule suspensions (CS), dusting products (DP), seed-dressing products, granules for broadcasting and soil application, granules (GR) in the form of microgranules, sprayable granules, coated granules and adsorption granules, water-dispersible granules (WG), water-soluble granules (SG), ULV formulations, microcapsules and waxes” [emphasis added].

1.D1 references several standard texts describing the various formulations, and goes on to describe methods (and ingredients) for making EC, SC and WG formulations.  The opponent submitted that D1 discloses the application of bixlozone to wheat, barley, rye, triticale, millet, rice or corn as a plant growth regulator.  They also noted that the present application acknowledges that bixlozone is known as a selective pre-emergence herbicide for weed control in corn, rice, sorghum, barley, rye and rape.  D1 does not explicitly disclose the weed species defined in Claims 10 and 11, but the opponent noted that D2 discloses that bixlozone is effective against some of the weeds defined in claim 10.   They submitted that the person skilled in the art would understand the teachings given in D2 to also apply to the claimed crystalline form and SC and WG formulations.  This submission would appear to require a mosaic of information from D1 and D2.  However, as discussed above I consider that D1 and D2 may be considered a single source of information for novelty purposes in relation to the preparation of of the crystal form of bixlozone, but this does not extend to other matters such as formulation and use.

2.The reference to the crop species in D1 which is relied on by the opponent relates to the use of bixlozone as plant growth regulators (preferably as a post-emergent treatment, and for example, as a culm stabilizer) for use in “crop plants like those mentioned above, preferably cereal plants, such as wheat, barley, rye, triticale, millet, rice or corn”.  I do not understand this to specifically disclose the use of bixlozone as a herbicide in these crop plants – rather the herbicidal and plant growth regulating uses of bixlozone appear to be described in D1 as separate and distinct applications.   No evidence was provided on this disclosure and what it would have meant to the skilled person.  Under the circumstances, while there may be a general reference to the features defined in claims 10 and 11, I do not consider that D1 provides the kind of sniper-like accuracy of disclosure required for anticipation.  I am therefore satisfied that claims 10 and 11 are novel in view of D1.

3.In summary, Claims 1, 2 and 9 lack novelty in view of D1.  Claims 3 to 7, 10 and 11 are novel as the specific methods defined by these claims are not disclosed by D1.

Inventive step

1.Section 7(2) of the Act sets out that an invention is taken to involve an inventive step unless it would have been obvious to the person skilled in the art in the light of the common general knowledge, either considered alone or together with information of the kind set out in section 7(3) of the Act.

2.Nicholas J recently provided a succinct statement of principles relevant to assessing inventive step in Hood v Bush Pharmacy Pty Ltd:

“Section 7(2) of the Act uses the word ‘obvious’ in the course of describing what must be established before an invention can be held not to involve an inventive step. Something may be ‘obvious’ in light of the common general knowledge, or the common general knowledge coupled with the relevant s 7(3) information, if it is ‘plain or open to the eye or mind, something which is perfectly evident to the person thinking on the subject’ or something which ‘would at once occur to anyone acquainted with the subject and desirous of accomplishing the end’.

An invention may also be obvious in light of the common general knowledge if the person skilled in the art faced with the same problem as the inventor would have taken as a matter of routine whatever steps might have led from the prior art to the invention, whether they be the steps of the inventor or not or (using the language of the ‘modified Cripps question’) if the person skilled in the art would be directly led as a matter of course to take such steps in the expectation that doing so might well produce a useful or better alternative to the prior art.  However, a claimed invention is not obvious merely because the person skilled in the art would consider that it was ‘worthwhile to try’.”

1.The modified Cripps question requires that there be a reasonable expectation of success.  This is explicit in the expectation that an approach “might well” succeed, and implicit in the characterisation of steps as those to be taken as a matter of routine.   However, success need not be guaranteed: “the relevant test is not knowing that steps will or would or even may well work, but merely expecting that the steps may well work.”  Further, it is possible that the skilled person might be directly led to try more than one alternative expecting that each may well produce a useful or desired result.

Submissions

1.The submissions made by the parties at the hearing included fairly extensive discussion of the issue of selection under the ground of novelty.  It was not necessary for me to go into detail on those submissions as I determined that D1 does not provide clear and unmistakable directions to the herbicidal use of SC and WG formulation in wheat and corn.  The opponent pressed the ground of inventive step against claims 10 and 11 for much the same reasons as for novelty.  For example,  one of the arguments went to the issue of whether the claimed formulations and methods possess any unexpected advantages or special character.

2.The opponent did not press the ground of inventive step based on the common general knowledge alone, but instead relied primarily on D1 or D1 in combination with D2.  To that end, the opponent submitted that:

·D1 discloses the use of form A in SC and WG formulations generally as a herbicide for controlling harmful plants. 

·D2 discloses the use of bixlozone in a range of weed species, including several listed in claim 10: Sertaria viridis (green foxtail), Convolvulus arvensis (field bindweed), Ipomoea lacunose (morning glory), Xanthium pensylvanicum (cocklebur), Echinochloa crus-galli (barnyard grass), Abutilon theophratri (velvetleaf), Avena fatua (wild oat), and Sorghum halpanese (Johnsongrass). 

·The prior art discloses crop safety for a range of crop species.  D1 discloses the use of   form A as a plant growth regulator in wheat, barley, rye, triticale, millet, rice or corn. 

1.The opponent argued that the mere formulation of a known crystal form into a SC or WG formulation for the purpose of controlling the growth of specific weed species in  specific weed crops, neither of which are selected on the basis of any rationale disclosed in the application, cannot be said to be inventive over the prior art.  They argued that there is nothing to suggest that the crystalline form would not work in the same way as any other form of bixlozone or that the selection of the weed and crop species in claims 10 and 11 is in respect of any special characteristic or unexpected advantage. 

2.The applicant submitted D1 discloses many possible formulations, and it is the selection of the SC and WG formulations out of “perhaps many possibilities which must be shown by [the Opponent] to be obvious, bearing in mind that the selection of the integers in which the invention lies can be expected to be a process necessarily involving rejection of other possible integers”.  The applicant also noted that the assertion that the person skilled in the art would have been directly led as a matter of course to try the SC and WG formulations is not supported by any evidence, including why the skilled person would have selected these formulations out of the many possibilities listed in D1.

3.The applicant went on to submit that in comparison to other formulations which do not comprise the polymorph, such as the EC formulation, the SC and WG forms achieve high herbicidal activity while remaining safe and environmentally friendly.  D1 does not disclose these advantages in the SC and WG formulations over any other forms in the context of the claimed polymorph.  I understand this to suggest that the special character of the claimed invention is a composite of these properties.  That is, the SC and WG formulations:

·can be more conveniently and efficiently used to prepare green and environmentally friendly agrochemical formulations, and

·have a high level of herbicidal activity, and

·are safer in wheat and corn.

1.The opponent pressed the ground of inventive step against claims 1, 2 and 9 to 11.  I have found that claims 1, 2 and 9 lack novelty, and it follows that they will also lack inventive step.  I have therefore limited my consideration to claims 10 and 11.

The problem to be solved

1.Neither party articulated a specific problem to be solved by the present invention.  This is of course not essential, but it does provide useful context for the inventive step consideration. 

2.The applicant’s position, including during prosecution of the application at examination, is that the present invention is a different polymorph to that disclosed in D1.  It would seem to me that the problem to be solved in the case of the polymorph per se is the provision of a new physical form of bixlozone that overcomes problems with existing physical forms that require special formulation processes to avoid melting and softening during processing which are said to be avoided with the present invention.

3.However, the applicant submitted that if claims 1, 2 and 9 were found to lack novelty then claims 10 and 11 would be novel and inventive on the basis of the selection of the SC and WG formulations from the numerous possible alternatives for certain advantageous properties.  Given my determination that the polymorph lacks novelty, this new line of argument requires a reconsideration of the problem to be solved since D1 discloses the thermostable crystal form of the invention, and therefore solves the problem set out above. 

4.The applicant submitted that the application teaches the discovery of the beneficial properties SC and WG compositions, particularly in terms of having a “high” level of herbicidal activity while remaining safe and environmentally friendly.  I consider that the problem to be solved can be taken to be the provision of improved herbicidal compositions comprising bixlozone that have these advantages.

The evidence

1.The opponent’s evidence was directed at the polymorphs per se.  No evidence in relation to agricultural formulation and herbicide use.  It would seem to me that the opponent proceeded on the assumption that a disclosure of the specific polymorph of bixlozone was considered a disclosure of agricultural formulations comprising such.  The applicant provided no evidence in the opposition. 

2.The onus lies with the opponent to make out their opposition, and it is incumbent on them to ensure that they adduce evidence that is supportive of their case.  Nevertheless, it would seem to me that the newly introduced arguments, at least in part, relate to whether the SC and WG formulations possess any unexpected advantages or special character based on the disclosure given in the specification.  Given the nature of the arguments, I consider that an assessment, albeit a limited one without the benefit of expert evidence from either party, may be made on the face of the document(s). 

3.To that end, certain matters that are acknowledged in the present application that do not appear to be in dispute and are consistent with disclosures in the evidence on file:

·Bixlozone is a known herbicide that has been “brought to the forefront of many companies in recent years due to its low volatility, compared with Clomazone which is prevailing in the herbicide market presently”.

·Formulations that are known in the art include solutions, emulsions, suspensions, powders, foams, pastes, granules, aerosols, and microcapsules, as well as polymer and coating compositions for seeds.  This appears consistent with the disclosure given in D1 of various standard texts describing such formulations and their preparation.

·The specification states that bixlozone has not been reported as a WG formulation. 

·Other formulations containing bixlozone have been reported, including SC formulations.  This seems to be consistent with the acknowledged disclosure of SC formulations of bixlozone given by D3 and D4.

·The specification also states that the use of bixlozone as a pre-emergence herbicide for weed control in wheat has not been reported.  I understand this to infer that the use of bixlozone as a post-emergence herbicide in wheat is known, as is its pre-emergent use in other crop species including corn, rice, sorghum, barley, rye, and rape.

1.I acknowledge that there has been no specific evidence adduced on these issues.  However, I note that crop safety is only tested in wheat and corn despite claim 10 further defining the use of the compositions in rape, rice, sorghum, barley and rye.  That is, there is no evidence provided in the specification to show that the selected compositions are safer than prior art compositions in these crops.  Claim 10 also defines a large number of weed species, despite the specification testing only two weed species.  There is no disclosure in the specification of any special property in these weed species that could be extrapolated to the broader group of weeds defined in claim 10 and not to other weeds.  All of the herbicidal tests are pre-emergent. 

2.The extrapolation of the embodiments given in the specification to the broader applications defined in claims 10 and 11 would appear to be based on the known properties of bixlozone.  If this were not the case, then claims 10 and 11 would lack support as the invention would not be enabled across the full scope of the claims.  Under the circumstances, I am satisfied that my determination can take the above matters into account and will proceed on that basis. 

Determination

1.As discussed previously, claims 10 and 11 define “applications” comprising the steps of providing a WG or SC formulation and using it for the control of unwanted weeds in the particular crop species.  Claim 10 further defines that the weed species treated comprise a group of weeds typical in wheat crops, a group typical in corn crops, and a third group of other weed species.  Claim 11 defines that the weed species are Stellaria media and Poa annua L.  A literal interpretation is that only these species are treated, but a practical interpretation is that at least these weed species are present in the crop.  Furthermore, the definition of the specific weed species adds nothing over the definition of the treatment of the crop species – that is, treatment of wheat or corn would treat weed species that are typical of those crops.  The consideration can therefore be limited to whether it would be obvious to use SC or WG formulations in the treatment of weeds in the particular crop species, rather than treatment the specific weed species.

2.I also note in relation to the applicant’s submissions concerning the invention involving the selection of integers from many possibilities that the claims are not limited to specific SC and WG formulations.  Rather, the claims are directed to the use of these classes of formulation as a whole.  The inventive step consideration is not in respect to the selection of certain excipients from many possibilities, but rather whether the selection of SC or WG formulations per se would be obvious. 

3.In that regard, D1 suggests the use of SC and WG formulations with form A.  Admittedly these formulations are given in a list of a number of alternative formulations, but D1 goes on to provide further details for a smaller subset of the named group, including possible excipients and manufacturing processes for SC and WG formulations (with reference to standard texts).  D2 also states that:

“As is well-known in the art, the formulation and mode of application of a toxicant may affect the activity of the material in a given application.  Thus, as a compound of this invention may be formulated as an emulsifiable concentrate, as a granule of relatively large particle size, as a wettable powder, as a solution, or as any of several other known types of formulations, depending on the desired mode of application.”

1.SC and WG formulations would each appear to constitute one of a group of known agricultural formulations that the skilled person would select according to the specific requirements of an application.  That is also consistent with the statement in the specification to the extent that various herbicidal formulations, including these two alternatives, are known in the art, and that bixlozone has previously been applied in SC formulations.

2.The SC and WG formulations are said to possess the advantage that they are “green and environmentally-friendly”.  This advantage stems from the properties of the thermostable polymorph, and in particular the melting point, which enables the SC and WG formulations to be made directly using the solid polymorph, though I note that the claims are not limited to formulations made in such a manner.  D1 also discloses that Form A has a melting point of 82°C and that it is the most thermostable polymorph.  It seems to me that it would be readily apparent to the skilled addressee that the polymorph disclosed in D1 would not suffer the disadvantages associated with lower melting point materials during processing.

3.However, the present claims are not directed solely to the formulations, but also include the steps of treating particular crop species.  The additional consideration is therefore whether the selection of the SC and WG from within the broader range of alternatives is for a special or unexpected property of these formulations in the particular crop species, or whether the selection is a mere choice from an obvious group of alternatives for properties that would be reasonably expected to provide a useful result in those crops.  This goes to the second and third advantages identified by the applicant, namely that the selected formulations have a high level of herbicidal activity while retaining a high level of safety to crops. 

4.Looking first at claim 10, the specification acknowledges that SC formulations comprising bixlozone are known, as is the use of bixlozone as a pre-emergent herbicide in corn, rice, sorghum, barley, rye and rape.  Moreover, contrary to the applicant’s submissions that the SC formulation has considerably higher herbicidal activity than the control agent and homogenous liquid formulations, in fact clomazone (the control agent), the EC formulation and the SC formulation have similar herbicidal activity in Stellaria media (50, 50 and 53% respectively).  The EC and SC formulations also have similar herbicidal activity in Poa annua L (43 and 50% respectively).  The SC formulation also shows a lower level of safety in wheat and corn than the EC formulation, and slightly lower level of safety in corn than the control agent clomazone.  No data is provided in respect of crop species other than corn and wheat, nor for any weeds other than Stellaria media and Poa annua L.  The applicant’s assertions that the SC formulations are unexpectedly better or advantageous in wheat and corn than homogenous liquid formulations are supported by the data provided in the specification.  The replacement of one form of bixlozone with another in such known applications would present no apparent difficulty or barrier to the person skilled in the art.  The skilled person would arrive at the claimed combination of formulation and use defined in Claim 10 without the exercise of any inventive faculty and in the expectation that it would provide a useful result.

5.I am therefore satisfied that Claim 10 lacks inventive step.

6.Turning to claim 11, the claim is limited to WG formulations and the crops to corn or wheat.  As noted above, the specification acknowledges that bixlozone has been used as a post-emergent herbicide in wheat, and that bixlozone has been used in the control of weeds in corn.  The opponent’s argument was essentially that it would be obvious to replace one form of bixlozone in a known formulation with a different form of bixlozone.  However, the specification states that bixlozone has not previously been used in WG formulations, and no evidence was provided to show that this was not the case. 

7.Furthermore, the WG formulation does show greater herbicidal activity than the SC and EC formulations.  In contrast to SC formulations, the specification states that the herbicidal activity remains above 80% when the bixlozone dose is reduced to 15.625 g/ha.  Admittedly this only appears to be the case with Stellaria media.  Activity of the WG formulation at this dose in Poa annua L. is 60%, which is within 10% of the SC formulation and 17% of the EC formulation.  At a higher concentration of 31.25 g/ha, the EC and SC formulations both have an activity of 70%, while the WG formulation has an activity of 82% in Poa annua L, and at 62.5 g/a.i the SC and WG formulations have equivalent activity in Poa annua L. 

8.The WG formulation is also said to retain high levels of herbicidal activity while remaining safe to crops.  However, the tests given in the specification suggest that the WG formulation is less safe in corn and wheat than the EC and control formulations.  Herbicidal activity is shown for only two weed species (Stellaria media and Poa annua L).  The examples, and the data shown relate only to pre-emergent use of a single WG formulation.  It is not clear how such limited tests can be conclusive of the formulations being unexpectedly better as herbicides and safer than any other formulation comprising bixlozone across the full scope of applications included in Claim 11.

9.Despite these concerns, the opponent adduced no evidence on this point and whether the person skilled in the art would consider that the herbicidal and crop safety properties of the WG formulation in corn and wheat are unexpected or of a special character.  Absent such evidence I am unable to conclude that the specific use of WG formulations of bixlozone in wheat or corn is a mere choice from a number of equally useful alternatives that would have been obvious to the skilled person at the relevant time. 

10.I am therefore satisfied, based on the evidence before me, that Claim 11 is inventive.

11.In summary, Claims 1, 2, and 9 and 10 lack inventive step.  Claims 3 to 7 and 11 are inventive.

Clarity

1.Section 40(3) requires that the claims must be clear.  A claim will lack clarity if a third party would be unable to ascertain whether an act would fall within the scope of the claim. 

2.The opponent pressed two issues under this ground.  The first issue relates to claim 2 and the definition of the crystal form with reference to the PXRD reflexes.  In particular, the claim defines that the PXRD spectrum must have at least three of the eight listed reflexes, and that the reflex at 2Ɵ=10.53+0.2° is strongest in intensity among the eight reflexes.  The opponent considered that this meant that the peak at 10.53 must be present by virtue of the fact it would not be the strongest if it were not present.

3.The opponent went on to submit that the relative intensities of peaks in a PXRD spectrum will depend on a range of factors during sample preparation.  Therefore the same crystal form may show different intensities for peaks in its PXRD depending on how the sample is prepared.  Therefore the person skilled in the art will not know whether or not a crystal form they have produced will fall within the scope of claim 2.  The application provides no guidance as to what relevant parameters should be used in the sample preparation for producing the required spectrum.

4.On the first issue, I agree that the requirement that the peak at 10.53 is the strongest in intensity implicitly requires that it must be one of the at least three peaks present in the PXRD spectrum.  But contrary to the opponent’s submissions, I do not consider this in itself impacts on the clarity of claim 2. 

5.On the second point, I share the concerns of the opponent in relation to the definition of the peak intensity.  The evidence shows that peak intensity is not a reliable means of distinguishing between polymorphs because of orientation effects and sample preparation effects.  This would not ordinarily be a significant concern as the evidence shows that the skilled person considers the position of the peaks rather than their intensity in order to determine whether two polymorphs are the same or different.  However, the applicant amended the claim to include this parameter during examination, and sought to rely on peak intensity in order to distinguish the present invention from the prior art.  That being the case, it would seem to me that if an unusual or “special” parameter is used in a claim to characterise an invention, then detailed information must be given to enable the skilled person to determine whether they are working within the scope of the invention.  In the present case that would include sufficient information such that any factors, including orientation effects and sample preparation effects, could be taken into account in the comparison.  Absent these details the skilled person would not be able to determine with any certainty whether they were working within the scope of the claim, and claim 2 therefore lacks clarity.

6.The opponent also raised issues in relation to the clarity of Claims 5 to 8.  The preamble of Claim 5 defines “[A] method for preparing a high-purity thermostable crystal of the 2-[(2,4-dichlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone compound (Formula I) according to Claim 1”.  The opponent noted that the term “high-purity” is not defined in the application, but that it states that “[T]he orthorhombic crystal of the 2-[(2,4-dichlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone compound (Formula I) prepared therefrom has a purity of greater than 99%.”  They argued that this is not expressed as a preferable embodiment and therefore the reference to high-purity in Claim 5 (and the dependent claims 6 to 8) is a reference to a purity of greater than 99%.  If the term, when properly construed in light of the specification, were to be interpreted as referring to anything other than a purity of greater than 99%, then Claims 5 to 8 would lack clarity for the same reasons that the term “substantially pure” was found to lack clarity by Jessup J in Albany Molecular Research Inc v Alphapharm Pty Ltd. 

7.As noted above, the applicant advised that they do not intend to press Claim 8, which specifies that the content of bixlozone is greater than 99%.  This arguably overcomes any issue that Claim 8 is redundant (assuming that the term high-purity is taken to mean purity of greater than 99%).  Inasmuch as the remaining claims that include the term high-purity lack clarity as suggested by the opponent, the present circumstances are different to those in Albany Molecular Research Inc v Alphapharm Pty Ltd as there is no expert evidence as to the ordinary meaning of high-purity in the art.  That aside, it seems to me that in addition to the opponent’s reliance on the value of 99%, there are other feasible interpretations.  For example, my understanding is that herbicides do not require the same level of purity as, say, pharmaceuticals, and technical grade materials may be sufficient for agricultural formulations.  The term high-purity may indicate that the material made by the process of the invention has greater purity than such materials.  Alternatively, the term may be intended to indicate that the polymorph of the invention is free of other polymorphs. 

8.A third alternative is that the term is intended to distinguish the process of obtaining the seed crystals (Claims 3 and 4), from those where the final product is obtained by recrystallisation (and therefore purification) of an intermediate bixlozone material, with the high-purity crystal form being the product of recrystallisation.  On balance, and absent any evidence on the matter, it seems to me that the third alternative is the meaning that should be given to the term.  I do not consider this results in any lack of clarity in the claims.

9.In summary, claim 2 lacks clarity.

Sufficiency

1.Section 40(2)(a) of the Act requires that the complete specification must disclose the invention in a manner which is clear enough and complete enough for the invention to be performed by a person skilled in the relevant art. In CSR, a three-step approach was taken to determine whether the specification provides a sufficient disclosure:

a.Construe the claims to determine the scope of the invention as claimed;

b.Construe the description to determine what it discloses to the person skilled in the art; and

c.Decide whether the specification provides an enabling disclosure of all the things that fall within the scope of the claims.

1.A key consideration is whether the claimed invention as a whole, or an individual feature of the invention, represents a principle of general application.  As set out in the Explanatory Memorandum, an enquiry is also made as to whether the invention can be performed across the full scope of the claim without an undue burden of experimentation or need for further invention.  To that end, an expanded approach was taken in Evolva to the third of the CSR enquiries:

(1) Is it plausible that the invention can be worked across the full scope of the invention?

(2) Can the invention be performed across the full scope of the claims without undue burden?

1.The approaches appear to have found approval with the Federal Court in, for example, Cytec v Nalco, though the concept of plausibility, and the requirement as it developed under European and UK law “that the patent should disclose not just what the invention is and how to replicate it, but some reason for expecting that it will work”, arguably sits with the concept of “speculative claiming” and support more generally.  The requirement that the invention is enabled across the scope of the claims applies to a range that is relevant to the invention – the essence or core of the invention – and not ancillary matters that do not relate to the core invention itself.

2.The opponent’s submissions separately related to the methods of making the seed crystal, recrystallisation using the seed crystals, and to the use of the formulations as herbicides as follows:

·Claims 3 and 4, to the extent that the claimed method encompasses an “enormous range” of different interacting parameters relating to the solvent, ratio of compound to solvent and the timing of heating and cooling steps used in the process for making the seed crystal.  The specification only demonstrates that only one very specific combination of these parameters is effective, and only certain solvents are said to work.  The skilled person would need to undertake a research project to understand precisely which combination would be effective to produce the desired result.

·Claims 5 to 7, to the extent that the claimed recrystallisation methods encompass a large number of different possible solvents, and no specific ratio of compound to solvent is defined.

·Claim 9 inasmuch as the application does not provide enough information for the skilled person to understand exactly which formulations and which crops and target weeds will work because not all of the different parameters are tested.  There is no principle of general application that based on the success of the limited specific tests means it would predictably work across all of the claimed combinations.

·Claim 10 to the extent that the claims cover all water dispersible granules and suspension concentrates, a long list of weed species and the use in corn, wheat, rape, rice, sorghum, barley or rye.  Similarly, while claim 11 is limited to certain crops and the two specific weed species, the claim covers all water-dispersible granules.

1.Many of the concerns raised by the opponent appear to constitute common general knowledge to the person skilled in the art of recrystallisation.  Thus, for example, the skilled person would, as a matter of routine trial and error, determine appropriate solvents and ratios for use in standard recrystallisation using a seed crystal. 

2.However, the process of making a seed crystal results in a specific product comprising a core of rhombohedral crystals and an outer layer of acicular crystals.  It would seem to me that specific solvent and recrystallisation conditions would be required to obtain a first crystallisation of rhombohedral crystals and then crystallisation of the acicular crystals.  The use of similar solvents to petroleum ether, and specifically alkanes and cycloalkanes, would seem a reasonable extrapolation.  However, the specification goes on to state that chloroform, hexane, methanol, ethyl acetate, toluene, acetone, DMF/water and other solvents/mixed solvents gave an oil or mixed solid with a long melting point.  The fact that hexane does not work suggests that it is not simply a matter of replacing petroleum ether with a similar alkane or cycloalkane solvent.  The specification provides no guidance as to what other properties the solvent must possess.

3.Similarly, Claim 3 defines a process of “slowly volatilising” the solvent though heating, cooling and re-heating.  At first blush this appears to involve repeated steps of heating to evaporate the solvent followed by cooling.  However, the process described in embodiment 3 involves heating to dissolve the crude starting material followed by cooling to 0°C for 18 hours, and then allowing the solution to stand at room temperature for 20 days, during which time the solvent evaporates.  Thus the conditions required to obtain the seed crystal are more specific than the general process of simply heating, cooling and re-heating in order to obtain the specific mixture of polymorphs in the specific arrangement.  Rather the process is specific to particular conditions, and while I do not consider they need to be limited to those given in Embodiment 3, I consider they should at least be limited to those given at page 4, lines 14 to 16.

4.In short, I consider the specification is insufficient for the invention defined in Claims 3 and 4 for the reasons given above.  Claims 5 to 7 are insufficient inasmuch as they rely on the seed crystal prepared in claim 4, but not for the other reasons asserted by the opponent.  The evidence shows that once the seed crystal is obtained, the skilled person would be able to determine appropriate conditions and solvents for its use in recrystallization by routine trial and error.

5.Turning to claims 9 to 11, it seems to me that the principle of general application relates to the use of a new form of bixlozone in herbicides.  Bixlozone is known to have herbicidal properties and to have good safety in some crops.  As indicated above under the ground of inventive step, the specific weed species named in claims 10 and 11 are typical in corn and wheat crops.  The processes for making the different herbicidal formulations and their use in controlling weeds in crops would appear to be known in the art.  There is nothing before me to suggest that there would be any difficulty in working the invention across the scope of the claims.  In short, I consider there is a clear and complete disclosure of the invention as defined in Claims 9 to 11.

6.The opponent also made submissions concerning “insufficiency by ambiguity” (otherwise known as insufficiency by uncertainty).  They submitted that this arm of UK law of sufficiency had been recognised in Australia (in Evolva).  I note that Evolva referred to insufficiency by ambiguity in reference to the different types of insufficiency that have developed in the UK.  There was no explicit recognition in Evolva that this type of insufficiency applies in Australia. Moreover, the concept of insufficiency by ambiguity, much like Biogen insufficiency, presumably developed as a consequence of the ground of clarity not being available post-grant in the UK. The ground of clarity is available at all stages Australia. Thus, while the Explanatory Memorandum to the RTB Act was intended to raise disclosure standards consistent with the principles espoused in Biogen, there is no suggestion that the legislative changes were also intended to conflate the grounds of sufficiency and clarity.

7.The submissions made by the opponent under this ground reiterated those set out for the clarity in relation to  the definition of peak intensity in the PXRD.  I have found that claim 2 lacks clarity.  I do not consider that any different result would be obtained under this ground. 

8.The opponent also submitted that the requirement that the crystal only share as few as 3 of the 8 listed 2Ɵ reflexes would be insufficient to identify a particular crystal form, and thus the skilled person would be unable to ascertain whether or not a crystal was within the scope of the claim.  The opponent did not raise this specific issue under the ground of clarity, though the arguments would seem to me to be consistent with the principles applicable to that ground.

9.But whether or not the principle of insufficiency by ambiguity applies in Australia, I do not share the concerns of the opponent in this regard.  The stringent US Pharmacopeia requirements ensure that pharmaceuticals are safe and effective for pharmaceutical use.  In contrast, there is a high degree of flexibility as to how applicants define their invention, provided the claims meet the various legal requirements for patentability.  There is a risk that if fewer peaks are used to characterise the invention then subsequent polymorphs could be found with similar peaks.  But sufficiency is determined based on the disclosure provided in the specification, interpreted in light of the common general knowledge as it existed at the relevant time.  In that regard there is no apparent difficulties for a skilled person to determine the PXRD of a crystal form.  Furthermore, none of the acknowledged prior art documents disclose a polymorph that meets the definition given in the claims, and there is no basis for me to take an approach where the claims are construed based on hypothetical future infringements.  In any case, Claim 2 is also dependent on Claim 1, which inter alia, defines the crystal with reference to the unit cell lattice dimensions and melting point.  The definition does not rely solely on the PXRD peaks.

10.In summary, the specification does not provide a clear enough and complete enough disclosure of the invention defined in Claims 3 to 7.

Support

1.Section 40(3) requires that the claims are supported.  At the heart of this consideration is the principle that the “extent of the patent monopoly, as defined by the claims, should correspond to the technical contribution to the art in order for it to be supported, or justified.”  In CSR Building Products Limited v United States Gypsum Company (CSR), the delegate took the following approach to determine whether the claimed matter is supported by the matter disclosed in the specification:

a.Construe the claims to determine the scope of the invention claimed.

b.Construe the description and the technical contribution to the art, that is how far the concept has carried forward the state of the art.

c.Decide whether the claims are supported by the technical contribution to the art.

1.The Federal Court has approved of this approach.

2.The opponent’s submissions for support were essentially the same as those discussed above for sufficiency.  The gist of their submissions was that the technical disclosure of the application is limited to one specific means of making the seed crystal (claims 3 and 4), two specific ways of recrystallising bixlozone to give the specific crystal form (claims 5 to 7), one specific SC formulation (claims 9 and 10), one WG formulation (claims 9 to 11) and one EC formulation (claim 9), and finally, testing the herbicidal activity and safety in two crop species and two weed species (claims 9 to 11). 

3.Given my determination under the ground of sufficiency and the overlap in the issues in dispute, I consider that I can deal with this fairly briefly.  I am satisfied that claims 3 to 7 lack support.  The technical contribution in relation to the preparation of the seed crystals is a specific method using specific conditions.  The methods claimed in claims 3 and 4 exceed this technical contribution for similar reasons to those given above under sufficiency.  Claims 5 to 7 lack support inasmuch as they rely on the seed crystal defined in claim 4.  However I am satisfied that the broader process of recrystallising bixlozone using a seed crystal would be supported. 

4.In the case of the applications defined in claims 9 to 11, the principle of general application is the use of the polymorph in the preparation of herbicidal formulations.  For similar reasons to those given under sufficiency, I am satisfied that claims 9 to 11 are supported.

5.In short, I consider that claims 3 to 7 lack support.  Claims 1, 2 and 9 to 11 are supported.

Utility

1.Section 18(1)(c) of the Act requires that the claimed invention be useful. A summary of relevant principles was provided by the Full Court of the Federal Court in Artcraft Urban Group v Streetworx:

“It is ‘no objection’ to the validity of an innovation patent granted under the Act that it is ‘commercially impracticable’. The utility of the patent depends upon whether, by following the teaching of the specification, the result claimed is produced.

The ‘basic principle’ of inutility is that if an invention ‘does what it is intended by the patentee to do, and the end attained is itself useful, the invention is a useful invention’ … What the invention is intended to do is a matter to be gathered from the ‘title and the whole of the specification.

Put another way, the two questions are: first, what is the promise of the invention derived from the whole of the specification?; second, by following the teaching of the specification, does the invention, as claimed in the patent, attain the result promised for it by the patentee? … Further, ‘everything’ that is within the scope of a claim must be useful, that is, attain the result promised for the invention by the patentee.” [citations omitted]

1.Section 7A also requires that an invention is taken to not be useful unless a specific, substantial and credible use for the invention (so far as claimed) is disclosed in the complete specification.  The Explanatory Memorandum to the Raising the Bar Act explained that:

·“specific” means a use specific to the subject matter claimed so as to “provide a well-defined and particular benefit to the public”;

·“substantial” means the claimed invention does not require further research to identify or reasonably confirm a “real world use”; “an application must show that an invention is useful to the public as disclosed in its current form, not that it prove useful at some future date after further research”;

·an asserted use will be “credible” unless there is evidence that the invention is inoperative (i.e., does not operate to produce the results claimed by the patent application) or there is reason to doubt the objective truth of the statements in the specification.

1.The opponent submitted that the application fails to meet the promise of the specification across the full scope of the claims in that:

·Claim 3 requires a “solvent A” selected from “alkanes and cycloalkanes”.  However the specification states that hexane, an alkane, will not perform the method of the claim.

·Claim 5 requires a “solvent B” selected from “alkanes, cycloalkanes, halogenated hydrocarbons, aromatic hydrocarbons, ethers, alcohols, esters, ketones, sulfoxides, amide solvents, and water”.  However Embodiment 7 shows that the method of Claim 5 does not work using ethanol, an alcohol.  This also applies to Claims 6 and 7.

·Claim 5 defines a method for “efficiently preparing a high-purity thermostable crystal”.  Pursuant to the opponent’s construction of the term “high-purity” being limited to purities greater than 99%, Claim 5 includes embodiments that do not meet the promise of the invention.  In particular, Embodiment 5 results in a product with a purity of 98.5%.

1.I agree with the opponent’s submission that the specification states that some solvents will not achieve the desired seed crystals using the defined methods, including hexane.  Claim 3 therefore lacks utility as it includes matter that does not work, and for which the specification does not provide additional information by which the skilled person could make the process work.

2.On the other hand, claim 5 defines the use of a seed crystal (prepared according to claim 4, which was not challenged) in a recrystallisation process.  The opponent referred to Embodiment 7, which found that recrystallisation did not occur when the starting material was dissolved in 25ml of ethanol.  However Embodiment 5, which uses 15ml of ethanol, successfully obtained the desired product when a seed crystal was added.  Thus, recrystallisation can be achieved using ethanol, provided the correct conditions are used.  Clearly some conditions for recrystallisation would not provide the desired outcomes, but it is well within the knowledge and abilities of the skilled person to determine these by routine trial and error based on the disclosure in the specification.  I do not consider that Claim 5, even in view of the negative result given by embodiment 7, lacks utility on this basis.

3.In summary claim 3 lacks utility.  However the opposition is unsuccessful on the ground of utility inasmuch as it relates to claims 5 to 7.

Conclusion

1.The opposition is successful on the grounds of novelty, inventive step, clarity, sufficiency and utility.

2.On balance of probability the crystal form defined by Claim 1 is the same crystal form as that described in D1.  Claims 1, 2 and 9 therefore lack novelty.

3.Claims 1, 2, 9 and 10 lack inventive step.  Claims 3 to 7 and 11 are inventive.

4.Claim 2 is not clear.

5.Claim 3 is not useful in that it includes matter which the specification states does not work.

6.The specification does not provide a clear enough and complete enough disclosure of the invention defined in claims 3 and 4.  The specification is also insufficient in relation to the matter of Claims 5 to 7 inasmuch as they rely on the seed crystal of claim 4. Claims 3 to 7 lack support for similar reasons.

7.The opposition is unsuccessful in respect of claim 11.

8.The applicant stated that they do not press claim 8, and so no determination has been made in respect of this claim.

9.The applicant has 2 months from the date of this decision to propose amendments (including deletion of claim 8) to overcome the above issues.

Costs

1.Costs generally follow the event.  I see no reason to depart from that approach.  I award costs according to Schedule 8 against the applicant, Zhejiang Zhuji United Chemicals Co., Ltd.

Dr L. F. McCaffery
Delegate of the Commissioner of Patents

Attachment 1

1. A crystal of 2-[(2,4-dichlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone compound (Formula I), characterized in that the crystal is an orthorhombic crystal, with a space group of P21 21 21 and lattice parameters of a=9.2301 (2) Å, b=11.0751 (3) Å, c=12.7554 (3) Å, α=90°,β=90°, and γ=90°; and a melting point of the crystal ranges from 83 °C to 85°C.

2. The crystal of the 2-[(2,4-dichlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone compound (Formula I) according to Claim 1, characterized in that the orthorhombic crystal shows, in X-ray powder diffraction reflexes determined as 2θ angle values using Cu-Kα radiation, at least three of the following reflexes:

(1) 2θ=10.53±0.2°
(2) 2θ=14.20±0.2°
(3) 2θ=15.92±0.2°
(4) 2θ=18.54±0.2°
(5) 2θ=19.80±0.2°
(6) 2θ=21.10±0.2°
(7) 2θ=24.92±0.2°
(8) 2θ=27.73±0.2°; and

the reflex at 2θ=10.53±0.2° is strongest in intensity among the eight reflexes.

3. A method for preparing a seed crystal of the crystal of the 2-[(2,4-dichlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone compound (Formula I) according to Claim 1 or 2, characterized in that a preparation process comprises dissolving a sub-thermostable monoclinic crystal of the 2-[(2,4-dichlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone compound (Formula I) in organic solvent A, slowly volatilizing the solvent A through heating, cooling and re-heating, crystallizing to produce a mixture of acicular crystals on the layer outside and rhombohedral crystals inside, and collecting the acicular crystals on the layer outside; the solvent A is one or more selected from the group consisting of alkanes and cycloalkanes.

4. The method for preparing the seed crystal of the crystal of the 2-[(2,4-dichlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone compound (Formula I) according to Claim 3, characterized in that the solvent A is a petroleum ether, a boiling range of the petroleum ether is between 60 °C and 90 °C.

5. A method for efficiently preparing a high-purity thermostable crystal of the 2-[(2,4-dichlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone compound (Formula I) according to Claim 1, characterized in that a preparation process comprises dissolving a crude product of the 2-[(2,4-dichlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone compound (Formula I) in solvent B by heating the solvent B to 40-100°C, then cooling to 10-30°C while adding an orthorhombic seed crystal of the 2-[(2,4-dichlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone compound (Formula I) prepared according to the method of Claim 4, crystallizing, and filtering to obtain a high-purity
thermostable orthorhombic crystal; the crude product is an oily liquid or solid; the solvent B is one or more selected from the group consisting of alkanes, cycloalkanes, halogenated hydrocarbons, aromatic hydrocarbons, ethers, alcohols, esters, ketones, sulfoxides, amide solvents, and water.

6. The method for efficiently preparing the high-purity thermostable crystal of the 2-[(2,4-dichlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone compound (Formula I) according to Claim 5, characterized in that content of 2-[(2,4-dichlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone compound (Formula I) in the crude product is not less than 80%; the solvent B is one or more selected from the group consisting of alkanes, halogenated hydrocarbons, aromatic hydrocarbons, alcohol solvents, and water; a weight/volume ratio of the 2-[(2,4-dichlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone compound (Formula I) to solvent B is 1:0.5-3.

7. The method for efficiently preparing the high-purity, thermostable crystal of the 2-[(2,4-dichlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone compound (Formula I) according to Claim 5 or 6, characterized in that the solvent B is one or more selected from the group consisting of petroleum ether, toluene, chloroform, ethanol, and water.

8. The method for efficiently preparing the high-purity, thermostable crystal of the 2-[(2,4-dichlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone compound (Formula I) according to Claim 5 or 6, characterized in that the content of the 2-[(2,4-dichlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone compound (Formula I) is greater than 99%.

9. An application of the crystal of the 2-[(2,4-dichlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone compound (Formula I) according to claim 1 or 2 in preparation of agrochemical formulations and control of unwanted weeds for protecting crops.

10. The application according to Claim 9, characterized in that the agrochemical formulations are a water dispersible granule or a suspension concentrate; the crops comprise corn, wheat, rape, rice, sorghum, barley or rye; the weeds comprise Echinochloa crus-galli, Digitaria sanguinalis, Setaria viridis, Eleusine indica, Cynodon dactylon, Phragmites australis, Cyperus iria, Polygonum L., Xanthium sibiricum, abutilon, Portulaca oleracea, Solanum nigrum, Chenopodiaceae, Acalypha australis, Malachium aquaticum, Amaranthus retroflexus, Portulaca oleracea, Amaranthus blitum, Conyza Canadensis, Elsholtzia ciliata, Cirsium japonicum, Cirsium setosum, Sonchus oleraceus L.,Eclipta prostrata, Calystegia hederacea, Parthenocissus tricuspidata, Commelina communis, Capparis spinosa L., Plantago asiatica, Medicago sativa L., Glycine soja, Alopecurus aequalis, Alopecurus japonicus, Beckmannia syzigachne Bromus japonicus Thunb, Poa annua, Avena fatua, Polypogon, Lolium perenne, Aegilops tauschii, Stellaria uliginosa, Galium spurium, Stellaria media, Cerastium arvense, Veronica didyma, Cardamine hirsuta, Polygonum lapathifolium, Vicia sativa, Capsella bursa-pastoris, Ixeris denticulata, Hemistepta lyrata, Oxalis corniculata, Euphorbia helioscopia, Convolvulus arvensis, Silene conoidea, Chenopodium serotinum L., Polygonum aviculare L., Rumex dentatus, Thlaspi arvense, Lapsana apogonoides, Lamium amplexicaule, Rotala indica, Abutilon theophrasti, AstilberivularisBuch.-Ham. ex D. Don., Ambrosia artemisiifolia, Leymus chinensis, Lolium multiflorum, Datura stramonium, Sorghum halepeme, Pharbitis Choisy, Elytrigia, Helianthus annuus, Polygonum convolvulus, Sinapis arvensis, Setaria glauca, green foxtail, Chenopodium album, Commelina benghalensis, Nigella damascena, Brachiara eruciformis, Cirsium arvense, Xanthium pensylvanicum, Papaver rhoeas, Matthiola incana, Setaria viridis sp. Pycnocoma, hairy beggarticks, Nigella damascena, horseweed, largecrabgrass, littleseed canarygras, Pennsylvaniasmartweed, pitted morningglory, sida spinosa L., Apera spica-venti, wild poinsettia and Cyperus esculentus.

11. The applications according to Claim 10, characterized in that the agrochemical formulation is water dispersible granule, the crops are corn, wheat; the weeds are Stellaria media, Poa annua L.

Attachment 2

D1	Present (Fig 6)	Difference
10.5	10.529*	0.029
11.8	-	-
12.4	-	-
14.2	14.198*	0.002
15.9	15.922*	0.022
16.8	16.741	0.059
17.3	17.337	0.037
18.5	18.543*	0.043
19.1	19.066	0.034
19.8	19.795*	0.005
20.3	-	-
20.7	-	-
21.1	21.099*	0.001
21.8	21.784	0.016
22.9	-	-
23.2	23.197	0.003
23.6	-	-
24.3	24.252	0.048
24.9	24.922*	0.022
25.9	-	-
26.3	-	-
26.7	26.723	0.023
27.7	27.725*	0.025*
28.0	-	-
28.4	-	-
28.6	28.554	0.046
29.0	-	-
29.3	29.364	0.064
29.5	-	-
30.5	-	-
30.7	-	-
31.6	31.887	0.287
32.1	-	-
33.0	-	-
33.3	-	-
33.6	-	-
33.8	33.807	0.007
34.2	-	-
34.3	-	-
34.9	-	-
35.9	-	-
36.4	36.346	0.054
36.7	-	-
37.0	36.998	0.002
37.3	-	-
37.7	37.731	0.031
38.2	-	-
38.7	-	-
39.3	-	-
-	43.958	-

Notes: differences of less than 0.01 are highlighted in yellow, differences of 0.01 to 0.05 are highlighted in green, and differences of less than 0.05 to 0.1 are highlighted in blue.  The single peak showing a difference of almost 0.3 is highlighted in grey.  The peaks given in Table 2 and Claim 2 of the present application are marked by an asterisk.