Nalco Chemical Company v W. R. Grace & Co. Conn

[2000] APO 4

OFFICIAL NOTICE

DECISION OF A DELEGATE OF THE COMMISSIONER OF PATENTS

Application  :          No. 624675 in the name of Nalco Chemical Company

Title:          Transition metals as treatment chemical tracers

Action:          Opposition to the grant of a patent by W.R. Grace & Co.-Conn.

Decision:          Issued

Abstract

The opposition is unsuccessful on all grounds.

1. Section 40

"Tracers" are defined as compounds that are used in a concentration that is not effective as a treating agent.  While the term "effective" is not a term of absolute precision, it still has a clear meaning in the art.  There could be argument in specific instances as to whether a concentration is in fact "effective", but any uncertainty at the periphery of the claims is not significant.

1. Obviousness

The problem, as assessed from a reading of the specification, was a desire to find improved tracers for liquid systems.  The declarants held opposing views on whether the use of transition metals would have been a matter of routine.  Both sets of views are logical in their own ways, and the evidence is evenly balanced.  Evidence of commercial success of the process of the application resolved the matter in favour of the applicant.

PATENTS ACT 1990

DECISION OF A DELEGATE OF THE COMMISSIONER OF PATENTS

Re:Patent Application No. 624675 by Nalco Chemical Company, and an opposition to the grant of a patent by W.R. Grace & Co.-Conn.

BACKGROUND

Patent application number 49151/90 was lodged on 6 February 1990 by Nalco Chemical Company (hereafter referred to as Nalco).  The application claims priority from US 315713, which was filed on 27 February 1989.  The application was examined by the Commissioner, and advertised accepted under the serial number 624675 on 18 June 1992.

W.R. Grace & Co.-Conn. (hereafter referred to as Grace) lodged a notice of opposition on 18 September 1992, and served a statement of grounds and particulars on 19 October 1992.  An amendment to the statement was allowed on 18 February 1993.  The service of evidence was completed on 29 March 1999.

Nalco proposed amendments to the specification during the process of serving evidence.  The amendment was opposed by Grace, but was allowed by the Commissioner following a hearing of that matter (see Nalco Chemical Company v W.R. Grace & Co.-Conn. [1998] APO 41).

The present matter was heard in Canberra on 7 December 1999.  Nalco was represented by Mr Denis Tuffery, Dr Ian Ernst and Dr Charles Tansey of Baldwin Shelston Waters, Sydney.  Grace was represented by Mr Adrian Ryan of counsel, assisted by Mr Andrew Dark of Davies Collison Cave, Melbourne.

THE RELEVANT LAW

The patent application was lodged before the commencement of the Patents Act 1990 (Cth), but this opposition was commenced after the commencement of that Act. By virtue of subsections 234(2) and 234(3) and regulation 23.3, this opposition is governed by the Patents Act 1990 (Cth), except that Part V of the Patents Act 1952 (Cth) replaces Chapter 5 of the Patents Act 1990 (Cth). Consequently the opposition is governed by Part V of the Patents Act  1952 (Cth) and the Patents Regulations 1991.

GROUNDS OF OPPOSITION

The statement of grounds and particulars identified four grounds of opposition, but only two were pursued at the hearing:  inventive step, and section 40.

THE EVIDENCE

The evidence in support of the opposition consists of declarations by Elizabeth Eadie, Ben Tornatore (the first Tornatore declaration), Donald Thomas Anderson, Hector John Cumming and Desmond John Regan.

The evidence in answer consists of declarations by Neville Stephenson, John Hoots, Donald Johnson (a first declaration and a supplementary declaration), Ian Thomas Ernst and Russell Henry Schroeter.

The evidence in reply consists of declarations by Andrew David Dark, Ben Tornatore (the second Tornatore declaration) and Neil Clifford Duncan.

Relevant parts of these declarations are referred to as appropriate in this decision.

THE SPECIFICATION

The description

The specification relates to liquid systems containing treatment chemicals, for instance cooling water systems.  Treating agents are commonly used, for instance scale inhibitors, and it is important to maintain an appropriate level of treating agent in the system.  The specification states that it is often difficult to directly measure the level of treating agent in the system.  A known alternative is to use a tracer compound which is more easily measured than the treating agent.  The specification provides a definition of a tracer:

"a tracer is a material used to trace another substance.  A tracer differs from a treating agent in that the tracer is either not effective as a treating agent, or is added at a concentration below that at which it would be effective for treatment."
[page 2, lines 5 to 9]

The specification refers to radioactive tracers [page 2] and chromium VI tracers [page 3] as previously known.

The present invention utilises a different class of tracer compounds:

"It has been discovered that transition metals, as a class, will satisfy the criteria for use as tracers if they are soluble in the liquid medium to be tested.  The transition metals have been found to exhibit minimal incorporation into equipment scale and typically exhibit much lower incorporation than the treatment chemicals used in the liquid systems.  Measuring the concentration of the transition metals provides more accurate information as to the volume of liquid and the amount of treatment agent added to the liquid system.  As a consequence, this invention provides methods for using transition metals as tracers and compositions containing transition metal tracers therein.

The transition metals have been found to perform better as tracers than some non-transition metals because their rate of incorporation into deposits in the system is much lower.  The most preferred embodiments of this invention employ transition metals which show lower incorporation into deposits in the system than Chromium VI, such as vanadium.  …

The transition metals Chromium VI and lead are excluded from those used in the present invention because their use is limited by governmental agencies."

[page 3, line 27 to page 4 line 24]

The specification goes on to list preferred properties of the tracer:

"the tracer selected is preferably not present in significant quantities within the waters tested.  In addition, the tracers selected must [be] quantifiable by tests that are not interfered with or biased by other chemical compounds normally present in the water to be tested.  The tracers selected are preferably inert and stable in the treatment water and do not reduce the activity of the treatment chemicals themselves.
           The tracers must be soluble in the waters to be tested and must be compatible with the treatment chemicals with respect to formation, storage, freeze-thaw recovery, etc.  Most importantly, the tracers must show a minimal incorporation into the equipment scale as compared to the treatment chemicals.  …  Last, the tracers should not present any sort of environmental problems in the event of discharge."
[page 2a, line 4 to page 3 line 8]

The claims

The opposition was directed to all claims.  However, the only claims that need to be considered are the independent claims.  These claims are reproduced in the Annex to this decision.

In essence, all of the independent claims are directed to a method of monitoring a liquid system containing a treating agent comprising the use of a tracer selected from a specified group of transition metal ions, and detecting the transition metal concentration.

SECTION 59(1)(i) -  Section 40 issues

Section 59(1)(i) makes section 40 issues a ground of opposition under the 1952 Act.  At the hearing Grace argued only one section 40 issue:  that the claims are unclear and do not define the invention in so far as they use the term "tracer".  "Tracer" is defined in the specification as a compound that is not effective as a treating agent, or is used in a concentration that is not effective for treatment.

It is well recognised that claims may use language that is somewhat imprecise so long as the claim is sufficiently precise having regard to the art:

"Lack of precise definition in claims is not fatal to their validity so long as they provide a workable standard suitable to the intended use."
[Minnesota Mining and Manufacturing Co v Beiersdorf (Australia) Ltd (1980) 144 CLR 253 at 274]

The Schroeter declaration states:

"For a given treatment situation and circumstances, those skilled in the art in the industry in Australia would generally agree to within 10% as to the minimum concentration of a particular component of a particular treating agent system which would be effective to meet the specified level of treatment performance.  I, and I believe others of ordinary experience in water treatment, would have no difficulty in distinguishing in practice between use of zinc or molybdenum as a treating agent and use of zinc or molybdenum as a tracer."
[paragraph 20.1]

The second Tornatore declaration states:

"Although some agreement may be reached in some cases, it is difficult to distinguish between what is considered a 'tracer' as opposed to a 'treating agent' without a clear indication of what is considered 'effective for treatment'."
[paragraph 9]

It appears that the term "effective" is not a term of absolute precision, but still has a clear meaning in the art.  There could be argument in specific instances as to whether a concentration is in fact "effective".  I consider that the claims are not unclear due to the use of the term "tracer", and that any uncertainty at the periphery of the claims is not significant.

SECTION 59(1)(g) -  Obviousness

Grace alleged that all claims are obvious.

The ground of obviousness is found in section 59(1)(g) of the 1952 Act:

"that the invention, so far as claimed in any claim, was obvious and did not involve an inventive step, having regard to what was known or used in Australia on or before the priority date of that claim;"

The law of obviousness

The law on obviousness under the 1952 Act is well established.  The question was explained by Aickin J in Wellcome Foundation Ltd v V.R. Laboratories (Aust.) Pty Ltd (1981) 148 CLR 262 at 270:

"It is as well to bear in mind that the question of obviousness involves asking the question whether the invention would have been obvious to a non-inventive worker in the field, equipped with the common general knowledge in that particular field as at the priority date, without regard to documents in existence but not part of such common general knowledge.  The question is not whether it was or would have been obvious to the inventor or to some other particular worker in the field."

The test for obviousness is whether it would have been a matter of routine to proceed from the common general knowledge to the claimed invention.

"It is still correct to say that a valid patent may be obtained for something stumbled upon by accident, remembered from a dream or imported from abroad, if it otherwise satisfies the requirements of the legislation.  What is important is that the patent itself should involve an inventive step, whether or not it was consciously taken by the patentee and whether or not it appeared obvious to the patentee himself.  The test is whether the hypothetical addressee faced with the same problem 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."
[Wellcome at page 286]

The parties agreed that the problem-solution approach is appropriate in the present case, so I will use that approach in this decision.  I note in passing that the problem-solution concept is evident in judicial decisions such as Minnesota Mining and Manufacturing Co v Beiersdorf (Australia) Ltd (1980) 144 CLR 253 (e.g. at 298: "this solution to the known problem") and Winner v Ammar Holdings Pty Ltd (1993) 113 ALR 63 (e.g. at 67: "The problem and the solution were readily apparent").

What is the problem?

The specification discusses at length the use of tracers in the prior art [pages 2 to 3], and the problems with the known tracers.  It is reasonable to infer that the problem addressed by the specification is to find better tracers for use in monitoring liquid systems.

The problem implies a knowledge of at least those prior art tracers admitted by the specification (i.e. radioactive tracers and chromium VI) and their limitations.

What is the common general knowledge?

Common general knowledge was defined by Aickin J in Minnesota Mining and Manufacturing Co v Beiersdorf (Australia) Ltd (1980) 144 CLR 253 at 292:

"The notion of common general knowledge itself involves the use of that which is known or used by those in the relevant trade.  It forms the background knowledge and experience which is available to all in the trade in considering the making of new products, or the making of improvements in old, and it must be treated as being used by an individual as a general body of knowledge."

There was some argument as to whether the use of chromium VI as a tracer was a part of the common general knowledge.  However, as chromium VI is part of the formulation of the problem, it is known for the purposes of this decision, and it is not necessary to determine whether it was also part of the common general knowledge.

There were no other submissions in relation to the common general knowledge.

Is the invention a matter of routine?

The key question is what would the person skilled in the art have done as a matter of routine in order to find a better tracer system.  It was known that chromium VI had been used as a tracer, and that chromium VI suffered from disadvantages.  There are statements by the declarants that it would have been a matter of routine to try different transition metals:

"Since those environmental problems were well known in Australia by 27 February, 1989, and both chromium VI and other transition metal compounds (as will be established hereinafter) were well known and/or widely used as corrosion inhibitors and/or tracers in Australia by that time, I consider it would have been obvious to substitute alternative soluble transition metal compounds as tracers in aqueous systems before that date."
[first Tornatore declaration, paragraph 22]

"I do not believe there can be any invention in merely naming the use of certain transition metals in a known method when other transition metals are known to or have been found to function in that method."
[first Tornatore declaration, paragraph 23]

These comments suggest that since chromium VI is a transition metal ion, it would have been routine to replace it with other transition metal ions.  There are other comments that it would not have been a matter of routine:

"I and my co-inventors had the idea of using as tracers selected compounds which had not previously been used before for that purpose.  The very idea of using such compounds as tracers in systems in which there are treating agents flies in the face of conventional thinking which is further demonstrated by the logic currently used by Tornatore.  The fact that some of the same or similar materials had previously been used as an active component in treating agent systems taught away from their use as tracers."
[Hoots declaration, paragraph 20]

"Thus in my opinion Tornatore applies hindsight to declare that it would be obvious to select a transition metal as a tracer.  Even then, there would be much of the periodic table to choose from.  While I agree with Tornatore that the problems were well recognised, I do not believe that any solution to the problem was obvious.
           Quite to the contrary, I would have been deterred from considering the group of metal ions claimed for use as tracers because of the use of many of them in treating agents."
[Schroeter declaration, paragraph 14]

"Prior to reading the proposed application, I would have thought that the mere fact that a metal such as molybdenum or zinc or chromium was useful as a component of a treating agent system would suggest that it would be unsuitable for use as a tracer.  Consequently, it would not have occurred to me to use such a metal as a tracer, for example in conjunction with a different treating agent but at a level below that at which it would itself be effective as a treating agent."
[first Stephenson declaration, paragraph 33]

The essence of these comments is that it would not have been routine to try materials that were known to be treating agents (when used in effective amounts).  The declarants do not explain why they have this view.  However, it seems likely that there would have been an expectation that a treating agent would be unsuitable as a tracer because it would not be inert.

The two groups of declarants hold opposite views on what would have been a matter of routine.  I was invited to consider that there was support for the routine nature of using other transition metals in an article in the Journal of the Cooling Tower Institute (1987) volume 8.  The article beginning at page 7 is titled "1986 Cooling Tower Institute's Annual Meeting Operating Seminar".  The article reports a question and answer session at the Annual Winter Meeting of the organisation.  The relevant portion of the article is a comment by Mr Kozelski:

"Ken Kozelski:  I've found that in combination with other organic inhibitors, the azoles and HEPD and polymers, molybdates are effective even at very low levels of 1 to 2 ppm.  I know it's an excellent tracer for these treatments and we get far better control of our organic treatment programs when we have this very low level of molybdenum and run the residuals based on the molybdenum test than we ever could using the HEDP drop test.  It is expensive, it runs about $4 a pound."

It was conceded that there is no evidence that this article was ever published in Australia, and that the meeting that is recorded took place in the United States of America during 1986.  It was argued that this is corroborative evidence that other people considered that the use of a transition metal as a tracer (in this case molybdenum) was a matter of routine.  I am not satisfied that I should regard this article as corroboration for a number of reasons.  First, it is not clear whether the person making the comment could be regarded as a person of ordinary skill in the art.  Second, it is not clear whether the same views would have been held in Australia.  Third, the article says that molybdenum is an excellent tracer, but it goes too far to say that it says anything about transition metals generally.  Fourth, it seems as though the molybdenum tracer is used at low levels that are still effective as an agent (admittedly in combination with other materials).  It is doubtful that this is a tracer in the sense that the present specification uses that term.  This article is not relevant to my decision.

I cannot reconcile the conflicting views of the declarants.  Both sets of views are logical in their own ways.  I consider that the concern expressed by Hoots, Schroeter and Stephenson is very significant, and must be answered.  Grace pointed out that chromium VI is known to have been used both as a treating agent and as a tracer.  To my mind, this suggests that the concerns are not as significant as they appear at first sight, but still leaves the matter finely balanced.

The final piece of evidence available to me is the commercial success of the process of the application:

"Since it's introduction in Australia 12 months ago [i.e. July 1992], the method has become widely adopted."
[Schroeter declaration, paragraph 36]

Commercial success is not conclusive, but it is indicative of an inventive step (see Meyers Taylor Pty Ltd v Vicarr Industries Ltd (1977) 137 CLR 228 at 239). In the present case, the evidence of commercial success persuades me that it is more likely than not that the use of transition metals was not obvious.

Conclusion on obviousness

Grace have not established that the invention is obvious.

CONCLUSION

The opposition is unsuccessful on all grounds.

Subject to any appeal, I direct that the application proceed to sealing.

COSTS

The power of the Commissioner to award costs is based on section 210 and regulation 22.8.  This power is discretionary, so I must take into account all relevant considerations.

The opposition was unsuccessful on all grounds.  In this situation it is appropriate to award costs against Grace.  However, Nalco amended the specification after the filing of the evidence in support.  This indicates that there were deficiencies in the specification that required correction.  The costs up until the amendment of the specification should be awarded against Nalco.

I award costs in accordance with Schedule 8 as follows:  up until the amendment of the specification costs are awarded against Nalco;  thereafter costs are awarded against Grace.

Dr S.D.Barker
Delegate of the Commissioner of Patents

Patent attorneys for the applicant  :  Baldwin Shelston Waters, Sydney

Patent attorneys for the opponent  :  Davies Collison Cave, Melbourne

ANNEX:  Independent claims of 624675

1. A method for monitoring a composition of a liquid system containing one or more treating agents which comprises the steps of:
   (1)  adding to the liquid system as a tracer a quantity of a transition metal compound, the transition metal being in the form of ions, cations, oxyanions or other associated complexes which are soluble in said liquid system, and being selected from the group consisting of yttrium, zinc, vanadium, manganese, nickel, cobalt, molybdenum, chromium (III), titanium, niobium, tantalum and tungsten, and
   (2)  detecting the amount of said transition metal within samples of the liquid system, said amount corresponding to the concentration of said one or more treating agents of said liquid system.

1. A method for monitoring the composition of an aqueous liquid system which contains an amount of treating agent that is susceptible to incorporation in equipment scale or degradation, said method comprising the steps of:
              (1)  adding as a tracer a known quantity of a transition metal compound selected from the group consisting of compounds of zinc, yttrium, vanadium, chromium (III), manganese, nickel, cobalt, titanium, niobium, tantalum, molybdenum, tungsten, and nickel to said aqueous liquid system, the quantity of transition metal added being proportional to the amount of treating agent added to the aqueous liquid system,
              (2)  quantifying the amount of said transition metal compound within samples of said aqueous liquid system, and
              (3)  correlating the quantity of said transition metal compound with the amount of said treating agent of said aqueous liquid system.

1. A method for monitoring a composition of a cooling water system which contains a treating agent wherein said method comprises adding a known quantity of a cobalt compound to said cooling water system which is proportional to the treating agent added, quantifying the amount of cobalt ions, cations, oxyanions or other associated complexes within samples of said cooling water system and correlating the quantity of cobalt with the amount of a treatment agent added to the system.

1. A method for monitoring a composition of a cooling water system which contains a treating agent wherein said method comprises adding a known quantity of a vanadium compound to said cooling water system which is proportional to the treating agent added, quantifying the amount of vanadium ions, cations, oxyanions or other associated complexes within samples of said cooling water system and correlating the quantity of vanadium with the amount of a treating agent added to the system.

1. A method for monitoring a composition of a cooling water system which contains a treating agent wherein said method comprises the following steps:

   (i)        adding a known quantity of a vanadium compound to said cooling water system which is proportional to the treating agent added;

   (ii)       quantifying the amount of vanadium ions, cations, oxyanions and other associated complexes within samples of said cooling water system;  and

   (iii)      correlating the quantity of vanadium with the amount of a treatment agent added to the system;

wherein said quantifying step includes treating at least one but not all of said samples of cooling water with H₂O₂ prior to adding a color reagent.

1. A method for monitoring a composition of a liquid system substantially as herein described with reference to any one of the accompanying drawing.

1. A method for monitoring a composition of a liquid system substantially as herein described with reference to any one of Examples 1 to 4.