Nautical Services Pty Ltd v Hitech Distillation (Australia) Pty Ltd

[1989] APO 32

In the Matter of the Patents Act 1952

‑ and ‑

In the Matter of Patent Application No. 549841 in the Name of NAUTICAL SERVICES PTY. LTD.

‑ and ‑

In the Matter of an Opposition thereto under Section 59 by HITECH DISTILLATION (AUSTRALIA) PTY. LTD.

DECISION OF A DELEGATE OF THE COMMISSIONER OF PATENTS
Background
         Patent application 549841 entitled "De‑Salinator for Brackish ‑ or Salt ‑ Water" originated from an International application No. PCT/AU83/00048 lodged on 27 April, 1983 which designated Australia, the present application arising following entry to the national phase in Australia.  The application derives priority from an earlier application lodged in Australia on 27 April, 1982.  Acceptance of the application and complete specification was notified in the Official Journal of 13 February, 1986, and Notice of Opposition was lodged on 9 May, 1986 by HITECH DISTILLATION (AUSTRALIA) PTY. LTD.
         The evidence stages in the opposition were completed on 29 November, 1988.  A hearing in the matter was held in Canberra on 19 April, 1989.  Mr J.G. Adams, patent attorney of Grant Adams & Company appeared for the applicant NAUTICAL SERVICES PTY. LTD., and Dr I. Ernst, patent attorney of Shelston Waters appeared for the opponent HITECH.  The inventor Mr I. Lloyd was also present.

The Notice of Opposition lists all available grounds of opposition specified in sub‑section 59(1).  However at the hearing the opponent relied only on the grounds of lack of novelty and obviousness.
Specification
         The invention relates to a de‑salinator for brackish ‑ or salt ‑ water and is stated to be particularly useful for marine applications.  The specification briefly refers to a number of problems arising in prior art marine de‑salinators as follows:

"Firstly, they use electric pressure pumps to operate the eductors.  These pumps require generators and/or alternators driven by the main and/or auxiliary engines of the watercraft for their power.  As the engines must operate at e.g. 3000 rpm to provide sufficient power, fuel is wasted when the engines are run at those speeds solely to generate electricity for the pumps.  Secondly, the pumps drive the eductors under pressure and bypass valves must be provided in an attempt to maintain the pressures in the eductors at a substantially constant value, therefore maintaining the condensation production rate at a constant.  Thirdly, the "still"‑type de‑salinators require regular de‑scaling and have a low output of fresh water while the osmosis‑ type require careful operation on start‑up to prevent membrane damage."

The stated objects of the present invention are directed to avoiding or reducing these problems.
         The invention is described in broad terms by way of a consistory statement which corresponds to accepted claim 1.  Claim 1 reads as follows:  

"1.A de‑salinator for brackish ‑ or salt ‑ water including:

a de‑salination chamber;

a heat exchanger in a lower portion of the chamber to boil the brackish ‑ or salt ‑ water in the chamber;

at least one condensor coil in an upper portion of the chamber, spaced from the heat exchanger by at least one baffle, the condensor coil or coils being arranged to condense de‑salinated water vapour, generated by the boiling of the brackish ‑ or salt ‑ water, to produce de‑salinated water; and

at least one outlet in the upper portion of the chamber for the de‑salinated water;

wherein:

the condensor coil or coils are cooled by passing the brackish ‑ or salt ‑ water through the condensor coil or coils, the brackish ‑ or salt ‑ water being drawn from a supply;  and

the water from the condensor coil or coils is drawn through an eductor by a suction pump, the eductor being connected to the chamber to produce at least a partial vacuum in the chamber."

The specification includes a detailed description of a preferred embodiment of the invention described with reference to three drawing figures.  The apparatus described is a marine de‑salinator for treating salt‑water having those features listed in claim 1.  Referring to some of those features in more detail, the heat exchanger is supplied with heated water from the cooling system of the main engine of the marine craft.  The condensor coils are cooled by salt‑water drawn from the sea.  To achieve this, a suction pump driven by the engine draws the salt‑water from the sea, through the condensor coils and then through an eductor before returning the then somewhat heated water via the pump outlet to the sea.  The side arm of the eductor is connected to drain‑off and overflow outlets in the lower portion of the chamber to enable overflow fluid and concentrated brine to be removed from the apparatus to sea, and to enable a partial vacuum to be created in the chamber.  The apparatus described also includes a second suction pump driven by the engine in a fresh water circuit which enables the de‑salinated water collected in the upper portion of the chamber to be drawn from the chamber via a second eductor and supplied to a storage tank in the fresh water circuit.
         The specification includes eight claims for the invention. Claims 2 to 7 are directly or indirectly appended to claim 1, and claim 8 is an omnibus claim which makes "reference to the accompanying drawings".
Evidence
         Considerable evidence was lodged by the parties in this opposition.  A brief summary of the declarations lodged and the number of exhibits thereto follows.

Statutory declarations were lodged by:

‑Ian Ernst, patent attorney (1 exhibit).

‑Farhad Shafaghi, an engineer with qualifications in Production Technology (9 exhibits).

‑Robert Morton, an engineering tradesman and design draftsman with experience in the design, manufacture, installation and repair of marine desalination units prior to September 1977 when he sold his company (4 exhibits).

‑Janet Surma, librarian.

‑Anthony Read, a qualified engineer (1 exhibit).

‑David Kerr, an employee and later a shareholder of a company, Auscoteng Pty. Ltd., now in liquidation (2 exhibits).

Statutory declarations were lodged by:

‑Ian Lloyd, Managing Director of the applicant company and a marine engineer and a marine surveyor with some 33 years engineering experience (1 exhibit).

‑Kevin Smith, Managing Director of a company which manufacturers, market and exports desalinators according to the present invention (3 exhibits).

‑Trevor Hazelwood, a qualified engineer and principal of a firm of Consulting Engineers (1 exhibit).

‑James Adams, patent attorney (4 exhibits).

Statutory declarations were lodged by:

‑Neville Stephenson, Professor in the Faculty of Physical Sciences at The University of Technology, Sydney.

‑Farhad Shafaghi (6 exhibits).

‑Brian Keane, an engineer with more than 30 years experience with the N.S.W. Water Board.

‑Leanne Hoctor, librarian.

‑Donald Davey, Managing Director of ONGA Pty. Ltd., a pump manufacturer (1 annexure)

‑Robert Morton, (2 exhibits plus 1 annexure).

I will now refer in some detail to the most significant parts of that evidence particularly those parts concerning alleged prior art desalinators.
(a)  Maxim‑type desalinators
     There are references in the evidence to certain desalinator units of a similar type but made or distributed by different companies being available in Australia before 1982.  Declarant Shafaghi refers to a "Maxim" Heat Recovery Desalinator manufactured by Riley Beaird (Exhibit FS2 is a brochure relating thereto which includes a diagram of the unit), a desalinator by Continental Emsco which from the brochure of Exhibit FS3 uses the Riley Beaird system, and a Clark Desalinator (Exhibit FS4 relates) which uses an arrangement analogous to the Riley Beaird system.  Morton declares that he designed and his company Waterstill Pty. Ltd. manufactured prior to September 1977 some 40 desalinator units identified as a Waterstill desalinator, which from the brochure of Exhibit RM1 also used an arrangement analogous to the Riley Beaird system.  I will simply refer to these various units as Maxim‑type desalinators.
          As to the construction of the Maxim‑type desalinator, it differs from the desalinator defined in claim 1 in one respect and that concerns the manner in which the condensor coil water is passed through the eductor.  The arrangement of the Maxim‑type desalinator is such that water is forced through the condensor coil and then the eductor by the use of a (preferably centrifugal) pump whereas the claimed device requires a suction pump to draw the water through the condensor coil and then through the eductor.
         Regarding the availability and knowledge of Maxim‑type desalinators in Australia, Shafaghi declares as follows in his first declaration:

"2.There is now shown to me Exhibit FS2 which I identify as a brochure relating to the "Maxim" Heat Recovery Desalinator manufactured by Riley Beaird.  Riley Beaird is only one of a number of companies which markets desalinators in Australia.  I have been informed that desalinators as described in the brochure have been widely known and used in Australia prior to April 1982 and have been used by the Royal Australian Navy and fisheries vessels.  I have been informed that a desalinator of the same design was marketed in Australia by Continental Emsco Watermakers (Exhibit FS3) prior to 1982.

3.There is now shown to me Exhibit FS4 which I identify as a brochure describing the operation of the Clark Desalinator.

4.I understand from enquiries I have made that the desalinators of Exhibits FS2 and FS4 became well‑known in Australia during the latter 1970s and that by 1980, the Maxim Desalinator (Exhibit FS2) and Clark Desalinator (Exhibit FS4) were widely known and used in Australia.  The design and operation of the Maxim Desalinator was common general knowledge among manufacturers, repairers and users of such equipment in Australia prior to 1982."

On the same topic, the relevant parts of Morton's first declaration are as follows:

"3.There is now shown to me Exhibit RM1 which I identify as a copy of a brochure as published by Waterstill Pty. Ltd. between 1972 and 1977.

4.Between March 1973 and September 1977 approximately 40 units of the type described in the brochure were made and sold by my company.  The sale of my Waterstill business to Aquachem included a large order from the Royal Australian Navy since completed by Aquachem.  I would expect that many of the Waterstill desalination units are still in service in Australia.

5.In addition to the desalination units sold by Waterstill Pty. Ltd. I would estimate that about 2000 brochures similar to that of Exhibit RM1 were printed and distributed by me by way of Sales promotion in Australia.

6.The Waterstill desalination unit described in RM1 was very similar in concept to the "MAXIM" desalinator manufactured by Riley Beaird with whom we competed in Australia.

There is now shown to me Exhibit RM2 which I recognize as a brochure describing a Riley Beaird desalinator.  Desalinators of that kind were well known to me and I believe would have been well known to all desalinator equipment manufacturers, repairers and to many users in Australia prior to 1977.

7.There is now shown to me Exhibit RM3 which I recognize as a brochure relating to a Clark Desalinator. Clark had been manufacturing desalinators of the kind described in RM3 for many years prior to 1977 and their equipment was well known to me and I believe would have been well known to other desalination equipment manufacturers and repairers in Australia before 1977."

There are other indications in the evidence that Maxim‑type desalinators were known and used in Australia prior to 1982.  For instance, Exhibit FS9 is a 1970 publication of the then Department of National Development entitled "Desalination ‑ a survey of Australian Plants" and from the pages exhibited reference is made to several Clark‑Maxim manufactured plants installed in Western Australia in 1968.  I note also that inventor Lloyd admits to "considerable knowledge and experience" of desalinators "including the 'MAXIM' desalinator by Riley Beaird".
(b)  Foley desalinator
     Exhibit FS5 is a copy of Australian Patent 459735 to Auscoteng Pty. Ltd.  This patent discloses a method and means to desalinate water.  The complete specification was lodged in September 1971 (application 33928/71) and was published in April 1973.  I will identify the desalinator of this patent as the Foley desalinator after its inventor Norman Foley.  I note from the evidence that Auscoteng was liquidated in 1984 and that the present opponent then became proprietor of the patent.
     The Foley desalinator disclosed in this patent differs in several respects to that of the present invention.  Firstly, it uses separate evaporator and condensor units connected via a steam pipe:  the present invention has these units arranged in a single chamber separated by a baffle.  Secondly, whilst in the Foley desalinator a pump in conjunction with an "air entrainment chamber" removes condensate from the system and in the process creates a reduced pressure in the evaporator, there is no disclosure that the cooling water for the condensor unit "is drawn through an eductor ... the chamber" as the desalinator defined in claim 1 requires.
     Details of the construction and operation of the pump and air entrainment chamber used in the Foley desalinator are given in Australian Patent 462145 also to Auscoteng Pty. Ltd., (Foley being the inventor), which was lodged as a copending application (No. 33927/71) to that giving rise to Patent 459735.  Patent 462145 at page 4 cross refers to patent 459735.  There were submissions made by Mr Adams reinforcing statements made in evidence for the applicant that the air entrainment device of Foley was not "an eductor".  Dr Ernst put the contrary argument based on opponent's evidence, particularly that lodged in reply.  In my opinion the opponent's view is correct ‑ the air entrainment device that Foley discloses and uses in his desalinator is in construction and operation an eductor.
     There has been evidence from Read and Kerr that a desalinator was manufactured in accordance with Patent 459735 in the early 1970's and was publically demonstrated in country towns across Australia.  Furthermore it is stated that Exhibit ALR 1 to Read's declaration is a report by consultants on the operation of that desalinator.  From the report, which is dated 22 February 1971, there are indications that the apparatus tested did accord with the arrangement in Auscoteng's Patent 459735.  Kerr who was associated with Auscoteng from 1967 until 1984 refers to the report and apparatus in these terms in his declaration.

"6.I confirm that the apparatus shown in the photograph and described in the report was in accordance with Patent Application No. 459,735.  That apparatus was taken around Australia in the early 1970s by salesmen of Auscoteng Pty. Ltd. who demonstrated the apparatus in country towns across Australia.  To the best of my knowledge, the report by Kinnaird Hill deRohan and Young Pty. Ltd. was not confidential and was in fact used by the company salesmen as a sales document.  .... The apparatus was associated with a patent number which made it possible for anyone interested to ascertain the principle of operation.  I do not now recollect how many units using the principle of Patent 459,735 were sold but believe that many were.  I believe that all those interested in the manufacture of desalinators in Australia and many ordinary citizens would have been aware of the Auscoteng desalinator and how it operated during the 1970s."

(c)  Marine Version Desalinator
         The evidence refers to a report entitled "Flow Chart Marine Version Waste Heat Desalinator" and to the construction of a Marine Desalinator.  Shafaghi's first declaration at clause 11 refers to Exhibit FS7.  This exhibit taken from Auscoteng's files consists of a copy of the report which forms Exhibit ALR 1 but includes 2 additional sheets describing a Marine Version desalinator.  Shafaghi states that it is believed that the sheets relating to the Marine desalinator were added to a copy of the report as per Exhibit ALR 1 by Auscoteng's personnel.
         The two sheets mentioned comprise a diagram of a desalinator together with a general description of the arrangement and its operation in a marine environment.  The desalinator described incorporates evaporator and condensor components within a single chamber with baffling therebetween. Two separate pumping circuits remove the waste brine and distilled water and additionally maintain a reduced pressure within the chamber.  Engine jacket water is circulated around the tubes of the evaporator unit.  Cold seawater is circulated around the condensor unit coils, then passes via a feed water heat exchanger to the bottom of the evaporator unit to thus constitute feed water for the evaporator.  Concentrated brine is removed from the evaporator by the brine pumping circuit which uses an electrically powered centrifugal pump in a circuit which diagramatically resembles and as briefly described corresponds in operation to, the Foley pumping circuit in Patent 462145.
         Kerr appends as Exhibit DK1 to his declaration lodged in evidence copies of similar sheets to those forming the additional sheets of Exhibit FS7.  He refers to Exhibit DK1 in these terms in his declaration dated 27 July 1987:

"4.There is now shown to me Exhibit DK1 which I recognize as a drawing of a Marine Version Waste Heat Desalinator which I recollect as having been in the possession of Auscoteng Pty. Ltd. more than ten years ago.  I cannot now remember who was the designer of that apparatus but recall that the apparatus was built and confirm that it operated as described in Exhibit DK1.  In particular, I confirm that the water from the condenser coil, after being drawn through the evaporator was drawn through an eductor by a suction pump, the eductor being connected to the chamber to produce at least a partial vacuum in the chamber.  I have indicated the eductor in the drawing and marked it "A".  The company was interested in sale of the apparatus shown in DK1 and made no effort to keep it confidential.  I do not know to whom the apparatus was eventually sold."

Submissions
         There were three main points put to me in submissions by Dr Ernst on behalf of the opponent.  Firstly it was submitted that Maxim‑type desalinators were part of the common general knowledge of the art in Australia prior to the priority date.  To support this contention, attention was drawn to the evidence of Shafaghi and Morton which, inter alia, indicates that various makes of desalinators of this type were manufactured and known in Australia for some time prior to 1982.  Secondly, it was submitted that the Foley desalinator was also part of the common general knowledge.  Thirdly, given such matters of common general knowledge the present invention lacked novelty either on the basis of the Foley desalinator together with common general knowledge (of Maxim‑type desalinators) or on the basis of Maxim‑type desalinators together with common general knowledge (of Foley desalinators).
         Mr Adams for the applicant, submitted that the opponent had not discharged its onus of establishing the grounds of opposition alleged, namely lack of novelty and obviousness.  He argued that the Foley desalinator and the Maxim‑type desalinator did not disclose the system arrangement of the invention as claimed in the opposed application, and he suggested that the obviousness attack appeared to be based on hindsight with little support in the evidence to arrive at a conclusion that the invention was obvious.  Mr Adams indicated that the applicant was prepared to acknowledge the fact that desalinators of the Foley and Maxim types were available in Australia prior to the priority date of the present invention. However in making such acknowledgement, Mr Adams did not specifically refer to the issue of whether such devices formed matters of common general knowledge in the art prior to 1982.

Common general knowledge
         In order to fully assess the opposition grounds of lack of novelty and obviousness, it is necessary to determine the common general knowledge in the art at the priority date of the present patent application, viz. 27 April 1982.  The only evidence relevant to this determination is to be found in that lodged by the opponent.  Dr Ernst submitted that the evidence indicated that both Maxim‑type desalinators and the Foley desalinator were part of the common general knowledge in the art.  The applicant has placed no evidence before me, nor argued the question of what constitutes common general knowledge in this case.  I therefore have uncontested evidence and submissions before me which will necessarily need to be considered with some caution.
         Quoted earlier in this decision are portions of Shafaghi's evidence to the effect that the Maxim desalinator was common general knowledge to those in the art prior to 1982.  I note however that Shafaghi's statements appear to arise from "enquiries" he had made in the industry and do not clearly represent his view arising from personal knowledge of these devices and of the art in Australia prior to 1982.  Thus I consider Shafaghi's evidence on this matter to be of low probative value.
Opponent's declarant Morton is in my view suitably qualified to identify matters of common general knowledge in the art. From his evidence (quoted earlier), it is clear that Morton was well aware of Maxim‑type desalinators prior to 1977 other than the Waterstill desalinator that his company produced. Morton makes the point that he believes desalinators of the kind manufactured by Riley Beaird and Clark would have been "well known" to all desalinator equipment manufacturers, repairers and users in Australia before 1977, some 5 years before the priority date of the opposed application. Morton also indicates that some 40 Waterstill desalinators were made and sold up to September 1977 and a "large order" from the Royal Australian Navy was completed after he sold his company. Furthermore he indicates that about 2,000 brochures relating to the Waterstill desalinator (Exhibit RM1) were distributed by him for sales promotion in Australia. I conclude from this evidence that desalinators of the Maxim‑type formed the background knowledge which was known and available to all in the relevant trade from about 1977 and thus were matters of common general knowledge at the priority date of the present invention (per Minnesota Mining and Manufacturing Co. v. Beiersdorf (Aust.) Ltd. (1980) 144 CLR 253 at 292).
         As to the question of whether the Foley desalinator was also part of common general knowledge there is the evidence of Mr Kerr (quoted earlier) and comments by Shafaghi.  Kerr states that apparatus in accordance with Patent 459735 was displayed around Australia and that some units were sold, and further states his belief that those interested in desalinators in Australia would have known of the Foley‑type desalinator and how it operated during the 1970s.  Shafaghi, after referring to Patent 459735 (in clause 9) and Patent 495414 (in clause 10), Foley being the inventor and Auscoteng Pty. Ltd. the patentee in each case, further remarks in clause 10 as follows:

"I have been informed that more than 40 desalinators in exact accordance with this design have been made and sold in Australia prior to 1982 by Auscoteng Pty. Ltd., a company which has since been liquidated and I believe that prior to 1982 this arrangement was common general knowledge in Australia among manufacturers and users of desalination equipment in Australia."

I note that Morton makes little reference to the Foley desalinator in his evidence except to indicate that he had obtained a copy of the specification of Patent 459735 prior to 1977 (clause 9, second declaration).
         Reviewing this evidence I am left in considerable doubt regarding the Foley desalinator being part of common general knowledge prior to 1982.  Whilst it seems clear from the evidence that a Foley desalinator was made, tested and exhibited, there is no authorative evidence from suitably qualified witnesses attesting to the fact that the Foley desalinator was common general knowledge : on this point Morton makes no comment and Shafaghi's comments seem to arise from what he has been "informed".  In such circumstances I cannot conclude that the Foley desalinator or for that matter patent specifications 459735 and 462145 were part of the common general knowledge in the art at the priority date.
Novelty
         I will consider the novelty question in turn against the prior art apparatus previously discussed.
(a)  Maxim‑type desalinators
         Referring first to the prior art Maxim‑type desalinators, the claimed apparatus differs in that a suction pump is used to draw the condensor coil water through an eductor whereas the prior apparatus utilizes a force pump upstream of the condensor coil and eductor.  In considering the novelty of the claimed apparatus it needs to be considered whether the difference results in a substantial contribution to the working of the device and is other than a mere workshop improvement inolving no inventive ingenuity.
         Morton, in his first declaration at clause 11, refers to the operation of an eductor associated with either an upstream or downstream pump.  Inter alia, he makes the following points:

"I have always considered that there would be no overall advantage in using a suction pump downstream of an eductor rather than a pressure pump upstream ...

...

Nothing in Application No. 549,841 leads me to believe that there is any surprising or real advantage to be gained by using a suction pump downstream of a venturi device instead of using a pressure pump upstream of the venturi device."

I note that the specification does refer to the objects sought to be met by the present invention although it is true to say that there is little reference to advantages arising from the use of a suction pump downstream of the eductor in the claimed apparatus.  However Lloyd in his evidence on behalf of the applicant advances several advantages arising from this arrangement.  These include:

‑reduced power demand by the pump as it is not producing unwanted pressure in the eductor lines,

‑less likelihood of water being forced via the eductor arm to the chamber since with the eductors being under suction there cannot be the pressure build‑up in the eductors,

‑the generation of a more efficient vacuum due to the suction pumps creating a smoother water flow through the eductor without aeration,

‑avoidance of unstable boiling in the chamber when a portion of the condensor coil water is directed as feed to the chamber prior to passing the eductor due to the absence of aeration of that water from using a suction pump (see clauses 6 and 9).

There is thus conflicting points of view between the parties on this particular issue : I note at this point that Lloyd's evidence regarding advantages was not the subject of rebuttal by the opponent in its evidence in reply.  On weighing up the evidence I am of the opinion that substantial advantages do arise from the use of a suction pump downstream of the eductor as claimed.  Furthermore I am not convinced from the evidence that the eductor/suction pump arrangement of the claimed invention is a mere workshop improvement or a question of design choice over the pressure pump/eductor arrangement of the Maxim‑type prior art desalinator.  Thus I find claim 1 novel over this cited prior art.
(b)  Foley desalinator
         As previously indicated, the Foley desalinator as described in Patent 459735 differs in several significant respects to that of the present invention, the main difference being that Foley draws condensate and concentrated brine from the apparatus via respective pump and eductor devices rather than condensor coil water as in the claimed apparatus.  Patent 462145 discloses in detail the pump and eductor device developed and used by Foley.  At page 4 of the specification of this patent the following paragraph appears:

"Hence it will be seen that the pump is ideally suited to desalinization plants and an example of its application to this use is described in Patent No. 459,735.  The pump in this application is connected to the outlet of the condenser to remove condensate therefrom and to maintain the required vacuum in the desalination plant."

In respect of the disclosure of the Foley patents and the novelty question Dr Ernst submitted inter alia:

"... one would have to be free to use what was put in the public domain by Foley in a Maxim‑type desalinator of common general knowledge or you would have to be free to read Foley and use his kind of pumping circuit where you have a pump downstream of an eductor with a common general knowledge type of desalinator to get the benefits that Foley was teaching which are that you can remove air efficiently and you can remove vapour and liquids that way."

Accordingly he submitted that claim 1 lacked novelty in the Griffin v. Isaacs sense in that any differences between claim 1 and that taught by Foley plus common general knowledge, or Maxim‑type desalinators plus Foley as common general knowledge, do not contribute to the working and are merely workshop improvements or variations falling within good design rather than invention.
         I do not agree with Dr Ernst's submission.  His submission regarding the use of published information and common general knowledge in my view goes far beyond that which is permitted with regard to novelty considerations.  For novelty purposes it is permissible to consider what a published patent specification or other published document would have disclosed to a person skilled in the art who read that document at the priority date of the claim in suit.  Such consideration does not permit an exercise of mosaicing of elements of public knowledge and common general knowledge to thereby formulate an overall different combination of features, as the submissions on behalf of the opponent implied.
         In the present case, the Foley patent specification 459735 describes a desalinator having a particular combination of features, and in the absence of evidence to the contrary I believe its disclosure to be limited to a desalinator so described.  As such it discloses a desalinator combination which as previously mentioned exhibits several constructional differences to the claimed apparatus.
         I therefore reject the argument by the opponent that the claimed invention lacks novelty in the light of the disclosures of Patents 459735 or 462145 concerning the Foley desalinator or by virtue of prior use of a Foley desalinator.  The differences that exist between the claimed invention and the Foley desalinator do not constitute, given the evidence, mere workshop variations.
(c)  Marine Version Desalinator
         The evidence in my view does not establish that the 2 sheets which describe a Marine Desalinator constituted published material prior to the priority date of the present application.  The disclosure of those sheets cannot therefore be used for novelty considerations.  Kerr declares that a marine version desalinator was built and later sold and that it operated as described in the exhibited sheets.  However from Kerr's evidence it is uncertain whether it was the description sheets or actual apparatus of the marine desalinator which was in the possession of Auscoteng Pty Ltd more than ten years previous (i.e. before 1977 given the date of his declaration).  In any event it has not been definitely established that the apparatus which was said to exist was in the public domain prior to the priority date.  Thus given the lack of clear evidence of publication of the material concerning the marine version waste heat desalinator or the availability of the device itself, I find that this material can not be used for novelty considerations.
(d)  Other novelty considerations
         In his evidence Morton refers to work he did on a vessel in the late 1970's.  He declares:

"I recollect that a suction pump was mounted downstream of an eductor in the Hawaiian vessel "Paka" which arrived in Australia in 1978 with an American "Watermaker" desalinator.  The arrangement on the "Paka" did not perform satisfactorily and I re‑fitted the entire installation."

y(In his second declaration he corrects the year to 1977).  However from this evidence the overall construction of the original desalinator fitted to this vessel is not made clear.  In the absence of such details I dismiss this material from further consideration.
Obviousness
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 as at the priority date (see Wellcome Foundation Limited v VR Laboratories (Aust) Pty Ltd (1982) RPC 343 at 346). Thus a consideration of the question of obviousness must be made against the background of the common general knowledge in the art in Australia at the priority date and without regard to documents in existence but not part of such common general knowledge.
         As I have earlier indicated, from the evidence lodged in these proceedings I have concluded that the Maxim‑type desalinator was part of the common general knowledge at the priority date.  I also concluded that the Foley desalinator and patent specifications 459735 and 462146 were not part of the common general knowledge.  Given this background common general knowledge, the question to be considered is whether at the priority date the desalinator of the invention comprising the combination of features claimed would have been obvious and would have involved no inventive step.
         No specific submissions on the obviousness question were made on behalf of the opponent at the hearing although in my view some of Dr Ernst's submissions concerning novelty were more relevant to the ground of obviousness.  I would add that the evidence lodged in these proceedings provide little assistance on this ground.
         When discussing the question of novelty I indicated how the claimed desalinator differs from the Maxim‑type desalinator and this concerns the incorporation of a suction pump downstream of the eductor in the condensor coil water line rather than a pressure pump upstream.  Morton's evidence suggests that such arrangements were alternatives and mere design choices, the operation and effect of each such arrangement being well known.  However the invention concerns desalination apparatus and there is no clear evidence that such arrangements are necessarily alternatives when applied to particular combinations of elements of a desalinator, nor has it been established that both such arrangements were matters of common general knowledge in the desalination art at the priority date.
         Thus the evidence is such that there is no material before me which indicates with any certainty that the present invention would have been obvious to a non‑inventive worker in the art.  It is well established law in an opposition action such as this that the onus rests with the opponent to establish the grounds of opposition alleged; in my view it has failed to do so with regard to the obviousness ground and I therefore reject the allegation of obviousness of the claimed invention.
Decision
         I have decided that the opposition has not succeeded on the grounds relied upon by the opponent.  Accordingly I dismiss the opposition and I direct that the application and complete specification proceed to sealing subject to any appeal.
         I award costs against the opponent.

(T.R. BRUHN)

Patent attorneys for the applicant: Grant Adams & Company, Brisbane