EMD Millipore Corporation v Asahi Kasei Medical Co., Ltd - [2020] APO 39

IP AUSTRALIA
AUSTRALIAN PATENT OFFICE
EMD Millipore Corporation v Asahi Kasei Medical Co., Ltd. [2020] APO 39

Patent Application: 2015309939

Title:Porous membrane

Patent Applicant:                   Asahi Kasei Medical Co., Ltd.
Opponent:  EMD Millipore Corporation
Delegate:  R Subbarayan
Decision Date:  21 August 2020
Hearing Date:  Written submissions completed on 8 April 2020

Catchwords: PATENTS - opposition under section 104 – allowability under subsections 102(1) and 102(2) considered – whether the amendments extend beyond the disclosure as filed – whether as a result of the amendments, the specification does not provide a clear enough and complete enough disclosure – whether as a result of the amendments, the claims are not supported or not clear – amendments allowable – cost awarded against the opponent

Representation: Patent attorney for the applicant: Watermark Intellectual Property Pty Ltd
Patent attorney for the opponent: Shelston IP Pty Ltd.

IP AUSTRALIA
AUSTRALIAN PATENT OFFICE
Patent Application: 2015309939

Title:Porous membrane

Patent Applicant: Asahi Kasei Medical Co., Ltd.
Date of Decision: 21 August 2020
DECISION
The s104 opposition is unsuccessful. I allow the amendments.
I award costs according to schedule 8 against the opponent.
REASONS FOR DECISION
BACKGROUND

Patent application 2015309939 in the name of Asahi Kasei Medical Co., Ltd. (the Applicant) was filed on 25 August 2015 as a PCT application (WO 2016/031834) and claims an earlier priority date of 25 August 2014. Following examination, it was advertised on 28 June 2018 as having been accepted. EMD Millipore Corporation (the Opponent) filed a Notice of Opposition to the grant of the patent on 28 September 2018 (the s59 Opposition).
Evidence in support was completed on 2 April 2019. The deadline for the applicant’s evidence in answer was 3 July 2019. On 6 June 2019, the opponent filed a statement of proposed amendments that included amendments to the description and claims of the accepted specification. On 9 July 2019 a Delegate of the Commissioner of Patents stayed the s59 Opposition pending the outcome of these amendments Following the receipt of comments from the opponent regarding the proposed amendments, the applicant filed a further statement of proposed amendments on 28 June 2019. A delegate of the Commissioner found the amendments to be allowable and the allowance was advertised on 15 August 2019. The opponent filed a Notice of Opposition to the allowance of the amendments on 15 October 2019 (the s104 Opposition). Neither party wished to file any evidence in relation to this s104 Opposition and hence this matter is being decided based only on written submissions that were completed on 8 April 2020.
THE RELEVANT LAW
The present opposition is governed by the Patents Act 1990 (the Act) as amended by the
Intellectual Property Laws Amendment (Raising the Bar) Act 2012 (the Raising the Bar Act). This includes an amendment to subsection 102(1) which precludes the inclusion of subject matter that extends beyond the original disclosure. Additionally, the changes brought about by the Raising the Bar Act to the disclosure and support requirements in subsections 40(2) or 40(3) are relevant since subsection 102(2)(b) precludes amendments after acceptance that result in the specification failing to comply with subsections 40(2) or 40(3).
Section 102(1) and (2) as amended by the Raising the Bar Act state:
(1) An amendment of a complete specification is not allowable if, as a result of the amendment, the specification would claim or disclose matter that extends beyond that disclosed in the following documents taken together:
(a) the complete specification as filed;
(b) other prescribed documents (if any).
Certain amendments of complete specification are not allowable after relevant time
(2) An amendment of a complete specification is not allowable after the relevant time if, as a result of the amendment:
(a) a claim of the specification would not in substance fall within the scope of the claims of the specification before amendment; or
(b) the specification would not comply with subsection 40(2) or (3).
Section 102(1) - Does not claim or disclose matter that extends beyond that disclosed at filing
The Explanatory Memorandum to the Intellectual Property Laws Amendment (Raising the Bar) Bill 2011 makes it clear that section 102 as amended is intended to prevent the addition of new matter to the description:
“The item introduces a provision preventing amendment of a complete patent specification after filing to add new matter that would go beyond the disclosure contained in the specification at its filing date. An applicant would not be able to amend the specification to add any material that the hypothetical skilled person could not directly derive by reading the information in the specification as filed.” [at 29]
Recently, subsection 102(1) was considered in Commonwealth Scientific and Industrial Research Organisation v BASF Plant Science GmbH (CSIRO)[1]. Beach J considered a number of decisions of the United Kingdom courts and saw no good reason not to follow them to the extent of applying analogous concepts to the present form of s 102(1)[2]. Beach J then noted as follows:
“215.   First, as has been pointed out, the test is a strict one.
216.     Second, subject matter will be impermissibly added unless the matter is clearly and unambiguously disclosed in the application as filed.
217.     Third, the required disclosure may be express or implied, but on any view must be clearly and unambiguously so. In this regard, a patent applicant is not permitted to add by amendment matter simply because it would have been obvious to the skilled person.
218. Fourth, context is important. A patent applicant cannot extract features disclosed in one context and introduce them into a specification stripped of that context. So, the concept of intermediate generalisation as discussed in the UK authorities applies to s 102(1) in its construction and application”.
[1] [2020] FCA 328.
[2] CSIRO at [214].
Thus the effect of subsection 102(1) is to prohibit an amendment to the specification which as a result would not have met the disclosure and support requirements of section 40 at the time of filing the specification. This is reflected in the Australian Patent Office Manual of Practice and Procedure (the MPP) at 2.23.8.2A:
“The effect of sec 102(1) is that an amendment must not add new matter that the hypothetical person skilled in the art could not directly derive by reading the information in the complete specification as filed and other documents prescribed by regulation 10.2A. However, where the person skilled in the art could directly derive the matter sought to be added to the specification from this combination of documents, an amendment will be allowable under sec 102(1).
The correct approach when considering whether an amendment would result in the specification claiming or disclosing new matter is to ask whether the person skilled in the art would, on looking at the specification as proposed to be amended, learn anything about the invention which they could not learn from the complete specification as filed (CSAF), in combination with the prescribed documents. This comparison is a strict one in the sense that subject matter will be added unless it is clearly and unambiguously disclosed in the relevant documents when read in combination.”
GROUNDS OF OPPOSITION
The Statement of Grounds and Particulars (SGP) filed on 14 November 2019, lists the grounds as follows:
1. Subsection 102(1)
The Amendment is not allowable because it does not comply with subsection 102(1) of the Patents Act 1990 (“the Act”) in that, as a result of the Amendment, the specification would claim or disclose matter that extends beyond that disclosed in the complete specification and abstract as filed.
2. Paragraph 102(2)(a)
The Amendment is not allowable because it does not comply with paragraph 102(2)(a) of the Act in that, as a result of the Amendment, a claim of the specification would not in substance fall within the scope of the claims of the specification before amendment.
3. Paragraph 102(2)(b)
The Amendment is not allowable because it does not comply with paragraph 102(2)(b) of the Act in that, as a result of the Amendment, the specification would not comply with subsection 40(2) or (3) of the Act.
SPECIFICATION
The present invention relates to a porous membrane useful for removing by filtration, viruses and other pathogens from fractionated plasma products and other biopharmaceuticals. The specification notes that in recent years there is a growing need for removal of small viruses such as parvovirus which have a diameter in the range of 18-24 nm. It further notes that porous membranes for removal of viruses should be able to remove viruses effectively without allowing contamination of foreign materials such as an eluate from the membrane into the fractioned biopharmaceutical and to recover protein such as albumin and globulin efficiently without clogging of the membrane.
The specification then states that the aim of the invention is to provide “a porous membrane by which a useful component such as protein can be recovered in a highly efficient manner while suppressing clogging during filtration of a protein solution and from which only a small amount of an eluate is eluted even when an aqueous solution is filtered”.[3]
[3] CSAF at [0016]
The specification then provides the following summary of the invention.
A porous membrane containing:
a hydrophobic polymer; and
a water-insoluble hydrophilic polymer, the porous membrane having:
a dense layer in a downstream portion of filtration in the membrane;
a gradient asymmetric structure wherein an average pore diameter of fine pores increases from the downstream portion of filtration toward an upstream portion of filtration; and
a gradient index of the average pore diameter from the dense layer to a coarse layer of 0.5 to 12.0.
The specification then describes preferred embodiments of the invention. In these embodiments the porous membrane comprise a base material made of a hydrophobic polymer which is then hydrophilized by allowing a water-insoluble hydrophilic polymer to exist at the surface of fine pores of the base material membrane. Examples of various hydrophobic polymers and hydrophilic polymers that can be used are then provided.
The porous membrane has a coarse structure in the upstream portion of filtration and a dense structure in the downstream portion of filtration. It is further described as having an asymmetric gradient structure in that the average pore diameter of the pores increases from the downstream portion of filtration to the upstream portion of filtration so that the larger particles will be filtered sooner than finer particles as the liquid passes through the membrane.
The specification then describes a method of calculating the average pore diameter using image analysis. This involves taking images of the cross-sectional surface of the membrane with a scanning electron microscopic across a series of adjacent visual fields in the membrane thickness direction. The pore portions and solid portions in each visual field are then subjected to binarization in order to calculate the average pore diameter in each visual field. Each visual field has a width of 1µm (micrometre or micron) in the membrane thickness direction and height of 2µm in the direction perpendicular to the membrane thickness direction. A visual field with an average pore diameter of 50nm (nanometer) or smaller is defined as a dense layer and a visual field with an average pore diameter of larger than 50nm is defined as a coarse layer.
Various examples of porous membranes prepared according to the present invention are then described and the results of the filtration using these membranes are presented in Tables 1 and 2.
The specification as accepted has 14 claims that are as follows:
1. A porous membrane containing:
a hydrophobic polymer; and
a water-insoluble hydrophilic polymer, the porous membrane having:
a dense layer in a downstream portion of filtration in the membrane;
a gradient asymmetric structure wherein an average pore diameter of fine pores increases from the downstream portion of filtration toward an upstream portion of filtration; and
a gradient index of the average pore diameter from the dense layer to a coarse layer of 0.5 to 12.0,
wherein an existence ratio of pores of 10 nm or smaller in the dense layer is 8.0% or less.
2. The porous membrane as claimed in claim 1 further containing:
an integrated permeability of immunoglobulin for 180 minutes of 8.0 to 20.0 kg/m² when 1.5% by mass of the immunoglobulin is filtered at a constant pressure of 2.0 bar; and
a ratio of immunoglobulin flux F180 at 180 minutes after starting filtration to immunoglobulin
flux F60 at 60 minutes after starting filtration of 0.70 or more.
3. The porous membrane according to claim 1 or 2, wherein a value of a standard deviation of pore diameters / the average pore diameter in the dense layer is 0.85 or less.
4. The porous membrane according to any one of claims 1 to 3, wherein an existence ratio of pores of larger than 10 nm and 20 nm or smaller in the dense layer is 20.0% or more and 35.0% or less.
5. The porous membrane according to any one of claims 1 to 4, wherein a porosity in the dense layer is 30.0% or more and 45.0% or less.
6. The porous membrane according to any one of claims 1 to 5, wherein the water-insoluble hydrophilic polymer is electrically neutral.
7. The porous membrane according to any one of claims 1 to 6, wherein a pure water permeation rate is 160 to 500 L/hr.m².bar.
8. The porous membrane according to any one of claims 1 to 7, wherein a bubble point is 1.40 to 1.80.
9. The porous membrane according to any one of claims 1 to 8, wherein a thickness of the dense layer is 1 to 8µm.
10. The porous membrane according to any one of claims 1 to 9, wherein the hydrophobic polymer is a polysulfone-based polymer.
11. The porous membrane according to any one of claims 1 to 10, wherein the water-insoluble hydrophilic polymer is a vinyl-based polymer.
12. The porous membrane according to any one of claims 1 to 11, wherein the water-insoluble hydrophilic polymer is a polysaccharide or a derivative thereof.
13. The porous membrane according to any one of claims 1 to 12, wherein the water-insoluble hydrophilic polymer is a polyethylene glycol or a derivative thereof.
14. The porous membrane according to any one of claims 1 to 13, for removing a virus contained in a protein solution.
THE PROPOSED AMENDMENTS
The claims as proposed to be amended differ from the claims as accepted as follows with the deletions denoted by ~~strikethroughs~~ and additions denoted by underlining.
1. A porous membrane containing:
a hydrophobic polymer; and
a water-insoluble hydrophilic polymer, the porous membrane having:
a dense layer in a downstream portion of filtration in the membrane, said dense layer having an average pore diameter of 50 nm or smaller;
a coarse layer adjacent to the dense layer at an upstream surface side of filtration in the membrane, said coarse layer having an average pore diameter of larger than 50 nm; and
a gradient asymmetric structure wherein an average pore diameter of fine pores increases from the downstream portion of filtration toward an upstream portion of filtration;
wherein a value of a standard deviation of pore diameters/the average pore diameter in the dense layer is 0.85 or less;
wherein a gradient index of the average pore diameter from the dense layer to a coarse layer of is
0.5 to 12.0, said gradient index being defined as the difference between the average pore diameter in nm of a visual field of the coarse layer and the average pore diameter in nm of a visual field of the dense layer, said visual fields being adjacent to each other, and said visual fields each being 1 μm in width of the membrane thickness direction;
wherein an existence ratio of pores of 10 nm diameter or smaller in the dense layer is 8.0% or less, and
wherein the pore diameters are calculated from binarized scanning electron microscope images of a cross-sectional surface of the membrane.
2. The porous membrane as claimed in claim 1 further containing:
an integrated permeability of immunoglobulin for 180 minutes of 8.0 to 20.0 kg/m² when 1.5% by mass of the immunoglobulin is filtered at a constant pressure of 2.0 bar; and
a ratio of immunoglobulin flux F180 at 180 minutes after starting filtration to immunoglobulin flux F60 at 60 minutes after starting filtration of 0.70 or more.
~~3. The porous membrane according to claim 1 or 2, wherein a value of a standard deviation of pore diameters / the average pore diameter in the dense layer is 0.85 or less.~~
4 3. The porous membrane according to ~~any one of~~ claims 1 to or claim 23, wherein an existence ratio of pores of larger than 10 nm and 20 nm or smaller in the dense layer is 20.0% or more and 35.0% or less.
5.4. The porous membrane according to any of claims 1 to 43, wherein a porosity in the dense layer is 30.0% or more and 45.0% or less.
6.5. The porous membrane according to any one of claims 1 to 5 4, wherein the water-insoluble hydrophilic polymer is electrically neutral.
7.6. The porous membrane according to any one of claims 1 to 65, wherein a pure water permeation rate is 160 to 500 L/hr.m².bar.
8.7. The porous membrane according to any one of claims 1 to 76, wherein a bubble point is 1.40 to 1.80.
9.8. The porous membrane according to any one of claims 1 to 87, wherein a thickness of the dense layer is 1 to 8 μm.
~~10.~~9. The porous membrane according to any one of claims 1 to 98, wherein the hydrophobic polymer is a polysulfone-based polymer.
~~11.~~10. The porous membrane according to any one of claims 1 to 109, wherein the water-insoluble hydrophilic polymer is a vinyl-based polymer.
~~12.~~11. The porous membrane according to any one of claims 10 to 1110, wherein the water-insoluble hydrophilic polymer is a polysaccharide or a derivative thereof.
~~13.~~12. The porous membrane according to any one of claims 1 to 1211, wherein the water-insoluble hydrophilic polymer is a polyethylene glycol or a derivative thereof.
~~14.~~13. The porous membrane according to any one of claims 1 to 1312, for removing a virus contained in a protein solution.
ARE THE AMENDMENTS ALLOWABLE
Both subsections 102(1) and 102(2) require consideration of consequences that follow as a result of the amendment. The expression “as a result of the amendments” was a feature of section 102 before the changes brought about by Raising the Bar Act and has been considered on many occasions. In RGC Mineral Sands Ltd v Wimmera Industrial Minerals Pty Ltd, Carr and Sundberg JJ discussed section 102(1) as it stood at the that time:
“That subsection requires one first to identify precisely what is the amendment. In this case that is done by identifying the difference between the specification as accepted (and as it stood at the hearing of the motion at first instance) on the one hand and, on the other hand, as the specification would read if amended in the manner sought. … The subsection focuses on the amendment proposed and it must be that amendment which has the result of pushing the claimed matter over the line defined by the expression [‘matter that extends beyond that disclosed’] … The key point to keep in mind is, as counsel for the respondent contended (in our view correctly), that the words ‘as a result of the amendment’ are not to be confused with the expression ‘after the amendment’.”
Therefore, the general approach to a consideration of subsection 102(1) is:
·firstly, identify the changes to the description and the claims by reason of the amendment proposed—what matter would be claimed or disclosed as a result of the amendment; and
·then, determine whether, as a result of the amendment, the specification would claim or disclose additional matter.
It is key to the approach to consider matter that is claimed or disclosed as a result of the amendment, and not matter claimed after the amendment.

Pre-existing defects in the specification are not relevant to the consideration of the allowability of amendments under section 102, as noted by Bennett J in Apotex Pty Ltd v Les Laboratoires Servier (No 2) (Apotex)[4]. Such deficiencies may be relevant to the opposition under section 59.
[4] [2009] FCA 1019 at [28]; 83 IPR 42.
The general approach to a consideration of paragraph 102(2)(b) is similar. Bennett J stated in Apotex (supra)
“… s 102(2)(b) requires:
1. Identification of the precise amendment sought by identifying the difference between the specification as it stood immediately before the amendment and the specification as proposed to be amended; and
2. Determination whether, as a result of the amendment, the specification would not comply with s 40(2) or s 40(3)”[5]
[5] [2009] FCA 1019 at [34]; 83 IPR 42
Although it is doubtful that all of the issues raised by the opponent arise “as a result of the amendment”, the applicant did not actively pursue this argument in their written submissions. For the purposes of this decision, I have therefore treated all of the issues raised by the opponent to the amendments to the claims and description as if they arise “as a result of the amendment”.
GROUND – Subsection 102(1)
Amendment 1 (Claim 1): said dense layer having an average pore diameter of 50 nm
or smaller;
a coarse layer adjacent to the dense layer at an upstream surface side of filtration in the
membrane, said coarse layer having an average pore diameter of larger than 50 nm;
The opponent submitted that the newly added feature of the coarse layer being at an upstream surface side of filtration is not clearly and unambiguously disclosed in the CSAF. Their reasons for this contention can be summarised as follows:
·The CSAF discloses the coarse layer as being provided in an upstream portion of the membrane and not on an upstream side of filtration.
·The meanings of the terms “upstream surface side” and “upstream portion of filtration” are not necessarily the same because the term “surface side” implies an external surface whereas “portion” implies a part of the membrane which can include external and internal regions.
The CSAF describes the location of the dense and coarse layers in a number of passages including the following (with my underlining):
In considering the intended purposes of the porous membrane as a separation/filtration membrane, the porous membrane is used in such a way that the upstream portion of filtration in the membrane has a coarse structure and the downstream portion of filtration in the membrane has a dense structure in the present embodiments.[6]
The porous membrane according to the present embodiments has a dense layer in the downstream portion of filtration in the membrane, and a gradient asymmetric structure in which the average pore diameter of fine pores increases from the downstream portion of filtration in the membrane toward the upstream portion of filtration, and a gradient index of the average pore diameter from the dense layer to the coarse layer of 0.5 to 12.0.[7]
A visual field having an average pore diameter of 50 nm or smaller is defined as a dense layer, and a visual field having an average pore diameter of larger than 50 nm is defined as a coarse layer. Figure 1 shows a result obtained by binarizing a specific SEM image.
Having a gradient asymmetric structure in which the average pore diameter of fine pores increases from the downstream portion of filtration in the membrane toward the upstream portion of filtration means that the average pore diameter of fine pores increases from the region where the average pore diameter is the smallest in the downstream portion of filtration toward the region where the average pore diameter is the largest in the upstream portion of filtration. In the present embodiments, the gradient asymmetric structure can be confirmed from digitization by calculating the average pore diameters from the analysis of the SEM images.[8]
In the case where the porous membrane is a porous hollow fiber membrane in the present embodiments, there is a case where the porous hollow fiber membrane has a coarse layer in the inner surface portion and has a dense layer in the outer surface portion, or there is a case where the porous hollow fiber membrane has a coarse layer in the outer surface portion and has a dense layer in the inner surface portion. In the case where the porous hollow fiber membrane has a coarse layer in the inner surface portion and has a dense layer in the outer surface portion, the inner surface portion is the upstream portion of filtration and the outer surface portion is the downstream portion of filtration. In the case where the porous hollow fiber membrane has a coarse layer in the outer surface portion and has a dense layer in the inner surface portion, the outer surface portion is the upstream portion of filtration and the inner surface portion is the downstream portion of filtration.[9]
[6] CSAF page 23, paragraph 5
[7] CASF page 25, paragraph 1
[8] CSAF page 27, paragraph 2
[9] CSAF page 27, paragraph 3
It is clear from these passages, that not only does the CSAF describe the dense layer and coarse layer as being adjacent and being provided in the downstream portion and the upstream portion respectively, it also discloses that the dense and coarse layers can be adjacent and be provided on the inner surface portion and the outer surface portion of the membrane. The critical requirement is that the coarse layer should be adjacent to and upstream of the dense layer. In my view, the disclosure of the CSAF is wide enough for the coarse layer to be anywhere in the upstream portion including the upstream surface portion.
The amended claim does not extend beyond the matter disclosed in the CSAF. This amendment is allowable.
Amendment 2 (Claim 1): said gradient index being defined as the difference between
the average pore diameter in nm of a visual field of the coarse layer and the average
pore diameter in nm of a visual field of the dense layer, said visual fields being adjacent
to each other, and said visual fields each being 1 μm in width of the membrane
thickness direction
The main thrust of the opponent’s submissions as to why this amendment is not allowable can be summarized as follows:
·The amendment seeks to define the gradient index in words rather than in terms of equation (1) disclosed in paragraph [0041] of the CSAF and in doing so defines matter that extends beyond that disclosed in the CSAF. In particular:
o   It introduces units of measurement for the average pore diameter as ‘nm’ (nanometers) whereas equation (1) defining the gradient index in paragraph [0041] of the CSAF does not specify any units for this parameter. Furthermore there is no basis to choose ‘nm’ as the unit when it also known in the art to use the unit ‘μm’ to express pore diameters.
o   It seeks to define the denominator “1” of equation (1) as being the width of the visual field when there is no such disclosure in the CSAF.
o   There is no term of the art called “gradient index” and hence the traditional meaning of gradient cannot be used to understand this term.
o   While the amendment introduces units for the pore diameters and the width of the visual field, the resulting gradient index is unitless.
The applicant on the other hand submitted that when the CSAF is read as a whole and equation (1) is interpreted in context, the amendment to claim 1 can be clearly and unambiguously derived from the CSAF.
“35.The reason for the denominator of '1' is not articulated, but considered in context, this refers to the fact that the difference in average pore diameter is being measured across a difference of 1 visual field, which represents a shift of 1 micrometre across the thickness of the membrane.
36.The Macquarie Dictionary relevantly defines the words 'gradient' and 'index' as follows:
Gradient: 3. Physics a. change in a variable quantity, as temperature or pressure, per unit distance.
Index: 8. Science a number or formula expressing some property, ratio, etc., of a thing indicated'
37.Read in context, the meaning of 'gradient index' is acceptably clear. It is presented as a dimensionless number, which is correct, since the 'gradient index' involves measuring the rate of change in average pore diameter (a length dimension), as a function of cross-sectional distance (also a length dimension), making the gradient index a dimensionless ratio.
38.The context provided by the CSAF shows that the pore diameters are to be measured in nanometres, while the relevant shift in cross-sectional distance of the comparator 'visual fields' is measured in micrometres. In relation to the invention, these are the only units described in the CSAF for each of those measures. The word 'index' is appropriately used because a ratio of 1000 to 1 is being used to express the 'gradient index' value. So, for example, a 'gradient index' value of 5.0 represents a rate of increase in average pore diameter of 5 nm for the 1 µm shift in cross-sectional depth (in the upstream direction), that is, from the defined 'dense layer' to the defined 'coarse layer'.
39.The ranges referred to above (0.5 to 12, 2 to 12 and 2 to 1014) only make sense as representing a difference in average pore diameter on a nanometre difference per shift of 1 micrometre, which constitutes a shift of 1 visual field. That is part of what informs a common sense construction of the claims, read within the context provided by the CSAF as a whole.”[10]
[10] Applicant’s submissions in answer at [35] – [39]
The fact that the applicant has chosen to claim the definition of the gradient index in words rather than in the form of the equation (1) disclosed in the CSAF is not objectionable as long as this definition can be clearly and unambiguously derived from the disclosure of the CSAF.
The CSAF makes a number of references to the gradient index including its relationship to the average pore diameters in the dense and coarse layers, including the following (with my underlining):
“The porous membrane according to the present embodiments has a dense layer in the downstream portion of filtration in the membrane, and a gradient asymmetric structure in which the average pore diameter of fine pores increases from the downstream portion of filtration in the membrane toward the upstream portion of filtration, and a gradient index of the average pore diameter from the dense layer to the coarse layer of 0.5 to 12.0.
In the present embodiments, the dense layer and coarse layer of the porous membrane are determined by taking images of the cross-sectional surface of a membrane with a scanning electron microscope (SEM) For example, a visual field is set horizontally to the membrane thickness direction at an arbitrary portion of the cross-sectional surface of the membrane with 50,000 magnifications. After taking the image of the one visual field that is set, the visual field for taking an image is moved horizontally to the membrane thickness direction and then the image of the next visual field is taken. By repeating the operation of taking an image, photographs of the cross-sectional surface of the membrane are taken without any space, and the photographs thus obtained are connected to obtain one photograph of the cross-sectional surface of the membrane. In this photograph of the cross-sectional surface, the average pore diameter in a range of (2 μm in a perpendicular direction to the membrane thickness direction) x (1 μm from the downstream surface of filtration toward the upstream surface side of filtration in the membrane thickness direction) is calculated every one micrometer from the downstream surface of filtration toward the upstream surface side of filtration”.[11]
“The gradient index of the average pore diameter from the dense layer to the coarse layer is calculated based on the first visual field as defined as a dense layer and the second visual field as defined as a coarse layer, the second visual field being adjacent to the first visual field. A place appears where a visual field is transferred from a visual field having an average pore diameter of 50 nm or smaller, the visual field defined as a dense layer, to a visual field having an average pore diameter of larger than 50 nm, the visual field defined as a coarse layer. The gradient index is calculated using the adjacent visual fields of a dense layer and a coarse layer. Specifically, the gradient index of the average pore diameter from a dense layer to a coarse layer can be calculated from expression (1) given below.
[11] CSAF at paragraph [0037]
[12] CSAF at paragraph [0041]
Gradient index of average pore diameter from dense layer to coarse layer= (average pore diameter of coarse layer (first visual field) - average pore diameter of dense layer (second visual field) ) / 1 ··· ( 1)”.[12]
In my view, the opponent is seeking to interpret equation (1) in isolation and not in the context of the disclosure as a whole. While the equation itself does not specify any units of measurement, it goes without saying that diameters are measured in length units. The passages from paragraph [0041] that I have referred to above clearly disclose that the pore diameter is measured in ‘nm’ and that the width of the visual field of each photograph is set at ‘1 µm’. The definition of what constitutes a dense layer and what constitutes a coarse layer is also referenced to the average pore diameter being measured in ‘nm’. Consequently, reading in context, it would be amply clear to the skilled addressee that in equation (1), the pore diameters of the pores in the dense and coarse layers are to be measured and expressed in ‘nm’. While it may also be known to express the pore diameters of porous membranes in other units such as ‘μm’, in the absence of a reference to any other unit other than ‘nm’ to specify the pore diameters in the CSAF, in my view the skilled addressee would clearly and unambiguously understand that the pore diameters in equation (1) are to be measured and expressed in ‘nm’ and not in other units.
While it is not in dispute that equation (1) does not specify what the denominator of ‘1’ refers to, the applicant has submitted that this refers to the visual field width of ‘1 µm’ and this has been expressed in the amendment of claim 1. The question to be answered therefore is whether the skilled addressee would directly and unambiguously understand that to be so from the CSAF.
The dictionary meaning of the term ‘gradient’ provided by the applicant, makes it clear that this term refers to the rate of change of a variable with respect to distance, which in the present case would be the rate of change of average pore diameter with respect to the width of one visual field as the average pore diameter is calculated for each visual field. While the term ‘gradient index’ may not be a well-known term in the art, the CSAF provides its own definition of this term in equation (1), which appears to generally accord with the definition of the term ‘gradient’ per se.
Equation (1) clearly states that the gradient index is a measure of the change in average pore diameter from the dense layer to the coarse layer (difference between the average pore diameter of the coarse layer and the dense layer) and this difference is then referenced to a measure of “1” without specifying what this measure stands for. However, in my view a skilled addressee trying to interpret the specification would not blindly accept the equation but would try and understand what this denominator signifies in the light of the disclosure of the specification as a whole. That is the role of the skilled addressee. In the present instance, the specification clearly highlights the difference in average pore diameters from the dense layer to the coarse layer as being critical for the performance of the invention. It then provides a method of calculating the average pore diameters in ‘nm’ across adjacent cross-sections or visual fields using images taken with a scanning electron microscope. It further explains that each visual field is chosen to have a width of 1 µm. As gradient is a measure of change of a parameter per unit distance, the skilled addressee would clearly and unambiguously understand that the denominator of “1” refers to the unit distance across which the average pore diameters are measured which in the present case is the width of 1 µm of each visual field. Consequently, in my view, the amendment to claim 1 to define the term ‘gradient index’ to include the reference to the width of each visual field as being ‘1 µm’ is no more than explicitly stating what the skilled addressee would clearly understand as to what the parameter ‘1’ in the denominator of equation (1) refers to.
This amendment to the claim and to the consistory statement in the description does not extend beyond matter disclosed in the CSAF and is therefore an allowable amendment.
The opponent also submitted that while the amendment provides units for the average pore diameters in the calculation of the gradient index, the values given for the gradient index are unitless (0.5 to 12.0), when they should actually be 0.5nm to 12.0nm as the gradient index appears to be no more than the difference in average pore diameters between the coarse and dense layers and this further introduces inconsistency between the amended claim and the CSAF leading to the amendment extending beyond the matter disclosed in the CSAF.
The applicant has argued that ‘gradient index’ is a dimensionless ratio.
Read in context, the meaning of 'gradient index' is acceptably clear. It is presented as a dimensionless number, which is correct, since the 'gradient index' involves measuring the rate of change in average pore diameter (a length dimension), as a function of cross-sectional distance (also a length dimension), making the gradient index a dimensionless ratio.
The context provided by the CSAF shows that the pore diameters are to be measured in nanometres, while the relevant shift in cross-sectional distance of the comparator 'visual fields' is measured in micrometres. In relation to the invention, these are the only units described in the CSAF for each of those measures. The word 'index' is appropriately used because a ratio of 1000 to 1 is being used to express the 'gradient index' value. So, for example, a 'gradient index' value of 5.0
represents a rate of increase in average pore diameter of 5 nm for the 1 µm shift in
[13] Applicant’s submissions in answer at [37] – [38]
cross-sectional depth (in the upstream direction), that is, from the defined 'dense layer' to the defined 'coarse layer'.[13]
I am not convinced that the lack of units for the gradient index values is a defect in the amended claim or that it introduces inconsistency. The CSAF has provided its own definition of the term ‘gradient index’ and how it is to be calculated and then expressed it as a unitless number. The proposed amendment merely continues to express it as a unitless numbers. I also find the explanation provided by the applicant convincing.
In my view, the introduction of units to express pore diameters and visual field widths without including units for the resulting gradient index does not introduce any inconsistency or disclose matter that extends beyond the disclosure of the CSAF. The gradient index was a unitless number even in the CSAF. This amendment is allowable.
Amendment 3 (Claim 1): wherein the pore diameters are calculated from binarized
scanning electron microscope images of a cross-sectional surface of the membrane
While the opponent accepted that the CSAF does disclose that the pore diameter can be calculated by a method of binarizing of scanned electron microscopic images of a cross-sectional surface of the membrane, they submitted that the disclosed method also clearly requires correction with a free-hand tool where the sections cannot be discriminated or where there is noise. This is therefore an essential or mandatory step of the binarization method that should have been included in the amended claim and by not providing this limitation in the amended claim, the claim would extend beyond the matter disclosed in the CSAF. They also submitted that if the average pore size diameter were determined using binarization only – i.e. without correction using a freehand tool – the average pore size diameter output would be different (compared with a procedure including the step of correction using a free-hand tool).

Paragraph [0038] of the CSAF that describes the binarization method reads as follows:
The average pore diameter is calculated by a method using image analysis. Specifically, pore portions and solid portions are subjected to binarization with Imagepro plus manufactured by Media Cybernetics, Inc. The pore portions and the solid portions are discriminated based on brightness, the sections that cannot be discriminated or noise is corrected with a free-hand tool. An edge section that forms a contour of a pore portion and a porous structure observed in the back of a pore portion are discriminated as a pore portion. After the binarization, a pore diameter is calculated from a value of an area per one pore assuming that the shape of the pore is a perfect circle. The calculation is conducted for every pore to calculate an average pore diameter every 1 μm x 2 μm range. It is to be noted that discontinuous pore portions at the ends of the visual fields are also counted.
When I read this paragraph, it is clear that the method of binarization involves the discrimination of pore portions and solid portions based on brightness. There is no evidence from the opponent to suggest that this is not a well-known method or that this method would not be understood by the skilled addressee. The specification then also states that in situations where the sections cannot be discriminated or where there is noise, then a free-hand tool is used to make necessary corrections. In my view, this does not change the basic steps of discrimination of pores and solid portions used in the binarization method. The free-hand tool appears to be an additional technique within the binarization method that is used in situations where the pores and solid portions cannot be discriminated based on brightness or where there is noise. If such situations do not exist, then the free-hand tool would not need to be used. I can see no basis to conclude as submitted by the opponent, that the use of the free-hand tool is a mandatory step that somehow changes the basic method of binarization, even if, as submitted by the opponent, the average pore diameter would be different if the free-hand tool corrections are not made in those situations where it is warranted.
I am satisfied that the method of binarization to measure the average diameter of the pores is disclosed in the CSAF and by amending claim 1 to include this method the claim is not defining matter that extends beyond the original disclosure. This amendment to the claim is allowable.
Amendment 4 (pages 8, 9 and 10): amendment of consistory statements
The opponent submitted that the amendment of the consistory statements to mirror the language of the amended claims also is not allowable for the same reasons as the amendments to the claims.
As I have found that the amendments to the claims are allowable under s102(1), it follows that the amendments to the consistory statements are also allowable for the same reasons.
Amendment 5 (pages 28, 20 and 62 of the description): insertion of “nm” into equation (1)
Again the opponent submitted that the inclusion of ‘nm’ into equation (1) extends beyond the disclosure of the CSAF and furthermore even if the numerator of equation (1) is in fact intended to have units then the denominator must also have the same units of length in order for the output of the gradient index to be unitless (as is specified in the claims and elsewhere).
Again as I have found similar amendments to the claims are allowable under s102(1), it follows that such amendments to the description are also allowable for the same reasons.
Ground 2 – Paragraph 102(2)(a)
As a result of the Amendment, a claim of the specification would not in substance
fall within the scope of the claims of the specification before amendment
The opponent submitted that the amended claims do not fall within the scope of the claims before amendment since something that was not an infringement prior to the amendment would be an infringement as a result of the amendment, particularly in view of the lack of clarity of the scope of the claims.
The proposed amendment to claim 1 adds additional features to claim 1 before amendment and does not delete any of the features of claim 1 before amendment. I have also found that the amended claims do not lack clarity. I am therefore satisfied that the amended claims fall within the scope of the claims before amendment.
3. Ground 3 – Paragraph 102(2)(b)
Subsection 40(2)(a) – As a result of the Amendment, the specification does not 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 and
Subsection 40(3) – As a result of the Amendment, the claims are not supported by
the specification
The opponent also submitted that as a result of the proposed amendment, the specification does not 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 and that further, as a result of the proposed amendment, the claims are not supported by the specification.
Firstly they argued that the term “a coarse layer adjacent to the dense layer at an upstream surface side of filtration” introduces a lack of clarity and is unsupported. They submitted that the definition of the coarse layer being at the ‘upstream surface side’ is unclear and not supported by the description. Furthermore the distinction between the terms “upstream portion” and “upstream surface” is not clear and consequently the specification does not 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.
I beg to differ. As I have discussed earlier, the CSAF does disclose the coarse layer can also constitute an upstream surface side of the membrane. In my view these terms are clear enough for the invention to be performed by a person skilled in the relevant art and are also supported. This argument fails.
Next, the opponent has argued that the definition of the term ‘gradient index’ in words including the introduction of the unit ‘nm’ in the amended claim confuses the reader regarding what is the gradient index and hence the specification does not 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.
Again I have earlier found that the definition of this term in the amended claim is clear and can be directly derived from the disclosure of the CSAF. For the same reasons it is also evident that the term ‘gradient index’ is supported by the description and the specification does not lack a clear enough or complete enough disclosure. This argument fails.
Next, the opponent submitted that the hand correction tool is an essential feature of the binarization method of discriminating pores and solid surfaces but the amended claim does not include this feature and without this feature the invention could not be performed and therefore the specification is not clear enough and complete enough.
Again I am not convinced. I have already found that the hand correction is only an optional feature for certain situations, and it does not in any way alter the basic steps of the binarization method. The amended claim does not therefore make the specification lack sufficiency or support.
Amendment 4 (pages 8, 9 and 10): amendment of consistory statements
The opponent also submitted that their arguments in respect of amendments 1 to 3 apply to amendments of the consistory statements on pages 8, 9 and 10.
As I have found that similar amendments to the claims are allowable under section 102(2)(b), it follows that such amendments to the description would also be allowable.
The opponent has also submitted that the insertion of “nm” into equation (1)) while the gradient index is defined in the complete specification as being unitless has changed the meaning of equation (1) and also made it unclear.
I have already discussed this issue when finding that these amendments do not extend beyond the CSAF and for the same reasons it is also clear that these amendments do not make the specification lacking a clear enough and complete enough disclosure.
CONCLUSION
None of the grounds of the s104 opposition have been made out. I am satisfied that all of the proposed amendments satisfy the requirements of s102 and are therefore allowable.
COSTS
As the s104 opposition is unsuccessful, I award costs according to schedule 8 against the opponent.
R Subbarayan
Delegate of the Commissioner of Patents