Hunter Wire Products Limited v Richardson Pacific Ltd., Lettela Pty Ltd and Polyscreen Pty Ltd

[1993] APO 52

official notice

decision of a delegate of the commissioner of patents

Application        :  No. 599524 in the name of HUNTER WIRE PRODUCTS LIMITED

Title             :  A SCREEN CLAMP ASSEMBLY

Action: Oppositions under section 59 of the Patents Act 1952 by RICHARDSON PACIFIC LTD., LETTELA PTY. LTD. and POLYSCREEN PTY. LTD.

Decision:  Issued            .  Claims found to lack compliance with section 40, to lack novelty and to be obvious.  Proposed amendments found to be not allowable.  Applicant given an opportunity to amend.

patents act 1990

decision of a delegate of the commissioner of patents

Re:Patent Application No. 599524 by HUNTER WIRE PRODUCTS LIMITED and opposition thereto under section 59 of the Patents Act 1952 by RICHARDSON PACIFIC LTD., LETTELA PTY. LTD. and POLYSCREEN PTY. LTD.

background

Hunter Wire Products Limited (Hunter) lodged patent application No. 599524 on 19 December 1988 as a complete-after-provisional to provisional specification PI 5955 lodged on 17 December 1987.  The application was advertised accepted on 19 July 1990.  Notices of opposition to the grant of a patent on the application were lodged by Richardson Pacific Ltd. (Richardson), Lettela Pty. Ltd. (Lettela) and Polyscreen Pty. Ltd. (Polyscreen) on 15 October 1990, 18 October 1990 and 9 October 1990 respectively.

As the application was both lodged and advertised as accepted before the commencement of the Patents Act 1990, the provisions of section 234(3) of the 1990 Act and regulation 23.3 are applicable and thus section 59 of the 1952 Act applies in relation to these oppositions.

All evidence was completed by 13 August 1992 except for further evidence which Lettela sought leave to adduce on 31 August 1992.  Leave to adduce further evidence was granted and all evidence in relation to this further evidence was completed by 23 February 1993.  On 30 March 1993, the Patent Office issued hearing notices to all parties indicating that the oppositions were set down for hearing in Canberra on 20 April 1993.

A letter dated 1 April 1993 accompanied by a statement of proposed amendments under section 104 of the Patents Act 1990 was filed by the applicant in the Patent Office on 5 April 1993. In letters dated 13 April 1993, the Patent Office informed all three opponents of the filing of the proposed amendments and provided the opponents with copies of the proposed amendments. At the time of the hearing, the proposed amendments had not been scrutinised to determine whether or not they are allowable.

The oppositions were heard in Canberra on 20 April 1993.  Hunter was represented by Mr. G. Turner, patent attorney of Spruson & Ferguson, Sydney, Richardson was represented by telephone by Mr. D. Mischlewski, patent attorney of Watermark, Melbourne, Lettela was represented by Mr. G. Cowin, patent attorney of Phillips Ormonde & Fitzpatrick, Melbourne, and Polyscreen was represented by telephone by Mr. S. Wilson, patent attorney of Griffith Hack & Co., Melbourne.

Although the notices of opposition included all or most of the grounds available under sub-section 59 (1) of the 1952 Act, the grounds relied on at the hearing were non-compliance with section 40 of the 1952 Act, lack of novelty and obviousness.

THE SPECIFICATION

The specification as accepted consists of two pages of description and one page of claims.

The description commences as follows:

"The present invention relates to industrial screens and more particularly to an assembly to retain an industrial screen panel fixed to a supporting structure.

Currently available methods of fixing screen panels in position are generally complex and require considerable time to dismantle to enable the screen panel to be easily removed and replaced.

It is an object of the present invention to overcome or substantially ameliorate the above disadvantage."

Then follows a consistory statement of the invention which is the same as the invention defined in claim 1.

A preferred form of the invention is then described with reference to the single sheet of drawings.

The specification ends with five claims as follows:

"1.  A screen panel support assembly comprising a support structure including a plurality of support bars arranged to engage the periphery of a screen panel, at least one clamp bar to extend along the periphery of the screen panel so that at least a portion of the panel is sandwiched between at least one of the support bars and the clamp bar, and wedge means to move the clamp bar into clamping engagement with the screen panel and to retain the clamp bar in its clamping position, said wedge means including a reaction surface fixed relative to the support structure and a wedge member located between the reaction surface and said clamp bar, with said wedge member having a wedge surface to contact said reaction surface, said reaction surface and said wedge surface extending longitudinally of said clamp bar and defining an acute angle with respect thereto so that upon movement of said wedge member in a predetermined direction said wedge member moves said clamp bar into clamping engagement with said panel.

2.  The support assembly of Claim 1 wherein each wedge means has a force transmitting surface abutting a force transmitting surface of the clamp bar, and the wedge surface and force transmitting surface of each wedge means converge in the general direction extension of the clamp bar.

3.  The support assembly of Claim 2 wherein the force transmitting surface of each wedge lies within a plane intersecting at an acute angle, a plane within which the wedge surface of the wedge means is located.

4.  The support assembly of any one of Claims 1, 2 or 3 in combination with a plurality of the screen panels, and wherein said panels are of a generally rectangular or square configuration with at least one of the clamp bars engaged with a longitudinal edge of the panel.

5.  A screen panel and support assembly therefor, substantially as hereinbefore described with reference to the accompanying drawings."

The claims as proposed to be amended are:

"1.  A screen panel support assembly comprising:

a plurality of supports for engaging an underside of a screen panel by its periphery;

at least one clamp bar, the clamp bar having a lower surface for contacting an upper surface of the screen, the clamp bar also having an upper surface which is angled transversely to a long axis of the clamp bar;

at least one double tapered wedge having flat sides, a lower surface of the wedge angled to correspond with the angle of the upper surface of the clamp bar so that when the lower surface of the wedge is in surface contact with the upper surface of the clamp bar, the sides of the bar and the sides of the wedge are parallel; an upper surface of the wedge inclined in the direction of a long axis of the wedge; and

one or more brackets, at least one corresponding to each wedge, the brackets each comprising a reaction surface against which a wedge may exert a force when exerting a clamping force on a screen and a wedge retaining surface which is generally perpendicular to the reaction surface.

2.The screen panel support assembly of claim 1, wherein:

the wedges and clamp bars are of the same width.

3.The screen panel support assembly of either of claims 1 or 2, wherein:

when in use with a screen the reaction surface of a Z-shaped bracket is acutely angled with respect to the screen.

4.A screen panel support assembly, substantially as hereinbefore described with reference to the drawing figures."

EVIDENCE

The evidence filed by all three opponents is directed at the claims as accepted.

The evidence supplied by Richardson consists of two declarations. One of the declarations has been made by Michael Yalden, an employee of Richardson, and includes seven exhibits.  The other declaration has been made by Heinz Kalbitzer, an employee of Polyscreen, and includes ten exhibits.  These same two declarations were also filed by Polyscreen together with a declaration by George Richard French which includes as an exhibit the declaration by Heinz Kalbitzer.  Mr. French is an employee of Boral Melwire, a company which distributes Polyscreen products.

The evidence filed by both Richardson and Polyscreen attempts to establish that both companies manufactured and sold, before the earliest priority date of the present claims, screen panel support assemblies similar to those defined in the present claims.  Samples of actual wedges have been included as part of the exhibits.  These wedges are oblong in shape with the top surface being sloped in a downward direction from one end of the oblong to the other end.  The evidence alleges that these wedges were used with angled reaction surfaces, clamp bars and support bars in a similar fashion to the arrangement defined in the claims as accepted.  The French declaration confirms that such systems were distributed by Boral Melwire prior to December 1987.  The Yalden declaration also states that wooden wedges similar to the samples provided were cut to provide an incline in two directions, namely parallel to the wall of the screen machine and laterally to the wall and that polyurethane wedges were also produced with inclinations in two directions.  A sample of such a polyurethane wedge has also been provided.

The Kalbitzer and French declarations also allege that these types of screen assemblies were so well known before the priority date of the present claims that they were part of the common general knowledge in the art.

The evidence-in-answer filed by Hunter is the same for all three oppositions.  The only evidence which relates to the Richardson and Polyscreen oppositions is part of a declaration made by Rodney Thomas Fox, an employee at the Newdell coal preparation plant and part of a declaration by Lionel George Kelly who is also presently employed at Newdell.

The Fox declaration provides some response to the Kalbitzer declaration.  Mr. Fox states that he cannot find anywhere in the Kalbitzer declaration a depiction of a Z-shaped bracket or a wedge with a laterally angled bottom surface or a clamp bar with a laterally angled top surface.  The Kelly declaration uses exactly the same wording as that provided in the Fox declaration in relation to the Kalbitzer declaration.

The evidence-in-support filed by Lettela consists of two declarations.

The first declaration which includes two exhibits has been made by Barry William Smith.  Mr. Smith does not indicate what his present occupation is but declares that he was a shift supervisor at the Newdell coal washery of Clutha Development Pty. Ltd. (Clutha) between 1976 and September 1987.

Paragraph 3 of the Smith declaration is as follows:

"THAT during the early years of my employment at the Newdell Coal Washery each Simonacco screening machine incorporated a screen deck system having an array of metal screen panels fixed to a support frame.  The screen deck system included a fixing arrangement which secured the screen panels to the frame but which allowed panel removal for maintenance and replacement when worn.

The fixing arrangement included the use of a series of side hold down slats.  Those slats extended along and overlaid the edge region of the screen panels, and lay against side walls of the support frame.  In this way, the edge regions were sandwiched between the overlying hold down slats and underlying parts of the support frame.  The slats were held in that position with a series of fixing wedges.  Two wedges were used to hold down each side slat.

Each side slat was a near square profile.

Each fixing wedge was elongate and positioned so as to extend along a side hold down slat between that slat and a bracket welded to the side wall of the support frame above the slat.  The bracket was L-shaped in profile, one leg being welded to the side wall with the other leg projecting outwardly from that the wall.

The wedge had a lower surface for bearing along an upper longitudinal surface of a side hold down slat and an upper surface which engaged against the underside of the outwardly projecting leg of the bracket.  The upper surface was angled toward the lower surface in a longitudinal direction of the edge so as to provide the wedge with a taper.  The wedge was driven longitudinally between the upper longitudinal surface of the side hold down slat and the bracket in a wedging action so as to force the slat downwardly into engagement with the screen panel.  As a result, the screen panel was clamped between the side hold down slat and the underlying support frame parts.  Reversal of this driving action removed the wedge and released the side hold down slat.

Each fixing wedge also had a pair of parallel side surfaces.  The lower surface of the wedge extended laterally perpendicular to the side surfaces.  However, the upper surface was angled laterally across the wedge, relative to the lower surface, from one side surface to the other side surface.  In use, the wedge was driven into position with the upper surface angling downwardly away from the side wall.  Thus, the higher side surface was located adjacent the side wall.  This tended to have the effect of pulling the wedge inwardly toward the side wall, and thus inhibiting the wedge from moving away from the side wall and out from between the bracket and side slat."

Mr. Smith then states that originally the wedges were made of wood but that during 1984 he was involved in replacing the timber wedges with polyurethane wedges.  The two exhibits to the Smith declaration consist of a photocopy of a letter of quotation addressed to Mr. Smith from Elastomers Australia and a photocopy of a drawing which has been numbered S 298.  The letter itemises a type of polyurethane wedge as part of the quotation and refers to the drawing number S 298.  The drawing depicts a wedge which has the same shape as that described in paragraph 3 of the Smith declaration.  Mr. Smith asserts that the wedges referred to in the quotation were supplied to Clutha in about December 1984 and other orders were filled between 1985 and 1987.

Paragraphs 9 and 10 of the Smith declaration are as follows:

1. THAT initially in late 1984 and early 1985 the polyurethane side slats and wedges were used in the same manner as the earlier timber side slats and wedges.  However, it became apparent to me and others that because the wedges had a relatively smooth outer surface finish compared with the timber wedges, they tended to work loose thereby releasing the side slats.  In an effort to reduce the movement, the outwardly projecting leg of the brackets was bent downwardly so as to extend at an angle which equated with the lateral angle of the upper surface of the wedges.  In this way, the upper surface was in an increased face-to-face engagement with the bracket leg.  In addition, the projecting leg tended to inhibit the wedge from moving away from the side wall.

1. THAT a further side slat and wedge modification I recall being adopted in the Simonacco Screening Machine  prior to September 1987 was the use of wedges having laterally angled lower surfaces which were in engagement with upper longitudinal surfaces of the side slats.  Again, the laterally angled surface sloped inwardly away from the side wall and downwardly toward the screen panel.  This had the effect of inhibiting the side slat from slipping relative to the wedge away from the side wall because the wedge forced the side slat downwardly toward the screen panel and also outwardly toward the side wall.

At about the same time, the brackets were also modified to provide an additional leg projecting downwardly from the outwardly projecting leg.  Thus, the bracket became a straightened Z shape in profile.  This additional leg functioned to prevent the wedges from shifting laterally away from the side wall and from beneath the bracket as would tend to occur with the adoption of the laterally angled lower surface.

I recall the side slats also being modified to provide the upper longitudinal surface with a lateral slope the same as on the lower surface of the wedges, so that those surfaces were in face-to-face engagement when the wedges were in their position forcing the side slats against the screen panels."

The second declaration filed by Lettela has been made by Andrew Lambert Bernadou and includes 5 exhibits.  Mr. Bernadou indicates that he is general manager of Elastomers Australia which is a Victorian business of Lettela.

Mr. Bernadou states that he was aware of the fixing arrangements for the Simonacco screening machines used at Clutha as early as 1984.  He describes these fixing arrangements generally using the same wording as in paragraph 3 of the Smith declaration.

Mr. Bernadou then confirms that his company supplied Clutha with wedges manufactured in accordance with drawing S 298.  One of the exhibits to the Bernadou declaration is a photocopy of an invoice which is dated 14 December 1984 and made out to Clutha and which lists 20 left hand and 20 right hand wedges.  Mr. Bernadou asserts that these wedges were manufactured in accordance with drawing S 298.  A further exhibit shows a photocopy of a purchase order with an order date of 18 June 1987 and a delivery date of 10 July 1987 in the name of BP Coal Australia (formerly Clutha) in which wedges are referred to by the part no. S 298.

Mr. Bernadou then declares that he was aware of various modifications made between 1985 and December 1987 to the screen panel clamping means for the Simonacco screening machines.  One modification that Mr. Bernadou indicates he was aware of was for the fixing wedges to be inverted so that the angled top surface engaged the upper longitudinal surfaces of the side slats.  Mr. Bernadou then indicates two more modifications he was aware of which correspond to the modifications described in the last two paragraphs of paragraph 10 of the Smith declaration.

Evidence-in-answer filed by Hunter consists of three declarations.

The Fox declaration, mentioned earlier, indicates that from April 1981 to July 1986, Mr. Fox (who is presently superintendent at Newdell) was employed at Newdell coal preparation plant as process engineer.  According to the declaration, the process engineer was accountable to the plant manager for coal quality, day-to-day process parameters and the optimisation and utilisation of raw coal resources to meet market requirements.  Mr. Fox then declares that it is not possible that the modifications referred to above in paragraphs 9 and 10 of the Smith declaration could have been performed at Newdell without Mr. Fox's knowledge.  Mr. Fox then asserts that he has no recollection of any of these modifications being made to the Simonacco screening machines.  The first time he saw such modifications was at a conference in 1989.

The second declaration filed by Hunter has been made by John Dallas Williams.  Mr. Williams does not state what his present occupation is but does indicate that, from August 1985 to May 1989, he served as plant maintenance engineer and as engineer in charge of both the Newdell and Howick facilities.  Mr. Williams further declares that his employment at Newdell required him to have extensive knowledge of each of the screening machines including the maintenance of each and in particular the clamping systems used with each screening machine.  Mr. Williams states that, prior to 17 December 1987, he had never seen, ordered, observed in inventory nor heard mention of any of the modifications referred to in paragraphs 9 and 10 of the Smith declaration.

The Kelly declaration, mentioned earlier, indicates that Mr. Kelly has been employed at Newdell since 1971 when he commenced his employment as a fitter welder.  However it does not provide any indication as to what position Mr. Kelly held from 1984 to 1987.  Mr. Kelly does say that, during the period of 1984 to 1987, he would have had regular if not daily experience with each of the screening machines at Newdell and would have been aware of any modifications made to any of the machines.  Mr. Kelly then asserts that it would not have been possible for any of the modifications referred to in paragraphs 9 and 10 of the Smith declaration to have been made without his knowledge.  Mr. Kelly declares that the first time he saw such modifications was about two to two and a half years ago.  (The Kelly declaration was signed on 20 March 1992.)

The evidence-in-reply filed by Lettela consists of a further three declarations.

A second Smith declaration indicates that Mr. Smith is not surprised that Messrs. Fox, Williams and Kelly have no recollection of the machine modifications because Mr. Smith did not discuss the modifications with them.  The modifications were not so important at the time that they were widely known within Newdell.  Mr. Smith further asserts that because the machines are dirty and noisy in operation the modifications would not be apparent to the casual observer.  The side slats are also often obscured by the ore being screened.

A second Bernadou declaration indicates that Elastomers Australia also supplied Clutha with modified side slats.  The slats were manually planed to provide a laterally extending slope on their upper surfaces.  The slats were molded without any internal steel reinforcement so that they could be more easily planed.

The other declaration filed as part of Lettela's evidence-in-reply has been made by Raymond Maxwell Woodgate who is production manager at Elastomers Australia.  Mr. Woodgate indicates that he was directly involved in the manufacture of replacement side slats and fixing wedges for the Simonacco screening machines at Newdell including the S 298 wedges referred to earlier.  Mr. Woodgate also indicates that he was directly involved, during the period of late 1984 to 17 December 1987, with the manufacture of the side slats referred to in the second Bernadou declaration.

The further evidence filed by Lettela consists of a statutory declaration by John Ronald Poole who is a senior maintenance engineer with Argyle Diamond Mines Pty. Ltd.  The declaration includes two exhibits which are copies of engineering drawings.

Mr. Poole asserts that the exhibited drawings illustrate screening units which were installed in the Argyle processing plant during 1985.  The drawings show a screen deck system in which the screen is fixed to the frame by a clamping arrangement.  The basic components of the clamping arrangement are pressure plates which are used to force the screen against a support bar, inverted L-shaped brackets and retaining wedges which are wedged between the brackets and the top of the pressure plates to force the pressure plates into clamping contact with the screen.  The brackets are attached so that the end of the horizontal leg of the inverted L is welded to the side plate of the mounting frame.  The vertical leg of the inverted L is spaced from the side plate of the mounting frame.  The reaction surface of the bracket which is in fact the horizontal leg of the inverted L is angled with respect to the upper surface of the pressure plate in a longitudinal direction.  The top surface of the wedge which comes into contact with the reaction surface of the bracket is also angled.  When the wedge is in place, it is retained in place by the vertical leg of the inverted L-shaped bracket.

In response to this further evidence, Hunter filed a statutory declaration by Ronald Keith McGregor who is an employee of Hunter.  Mr. McGregor states that the wedge arrangement referred to in the Poole declaration is for a stationary screen assembly and would not be suitable for a vibrating screen assembly.

SUBMISSIONS

The Richardson opposition

Mr. Mischlewski, on behalf of Richardson, indicated at the hearing by telephone that he would rely on written submissions which he had lodged before the day of the hearing.  As the written submissions were not available at the time of the hearing, I agreed to a request that the applicant be given fourteen days from receipt of these written submissions to provide a written response.  The applicant duly provided submissions in response within the required time.

Mr. Mischlewski's submissions are directed not only to the claims as accepted but also to the claims as proposed to be amended.

Mr. Mischlewski submits that, because the specification as accepted provides no indication of why the invention was made and what advantages arise out of the invention, I can only conclude that the modifications made in the specification constitute mere workshop variations and do not constitute an invention.

Mr. Mischlewski then refers to various paragraphs in the Yalden declaration to illustrate what he believes to be the prior art.  He concludes that all that Hunter has done is to make a non-inventive modification to existing clamping bar arrangements especially as there is no evidence that there was any difficulty with existing clamping bar arrangements.

Mr. Mischlewski then turns to the question of prior publication by use.  He again refers to the Yalden declaration and points out that paragraphs 14 and 15 indicate that both wooden and polyurethane wedges were made with inclinations in two directions.  Paragraphs 6,7, and 8 establish that Richardson had supplied and installed in Australia prior to the priority date of the claims as accepted, clamping arrangements which were effectively identical to those in the present patent specification.

Mr. Mischlewski points out that none of the declarations filed as evidence-in-answer comments on the Yalden declaration.  It remains unchallenged and therefore I should accept as fact the statements in the Yalden declaration.

Mr. Mischlewski briefly refers to the claims as proposed to be amended and submits that the brackets and wedges described in paragraphs 8, 14 and 15 would fall within the scope of the amended claims and therefore this establishes lack of novelty.

Mr. Turner made a brief submission at the hearing in relation to the Yalden declaration.  He referred to the polyurethane wedges described in paragraph 15 and noted that no dates of installation had been provided in relation to these types of wedges.

In written submissions filed as a response to Mr. Mischlewski's written submissions, Mr. Turner indicates that Hunter has decided to pursue the proposed amended claims only.  As a consequence his submissions are directed to those claims.

Mr. Turner then submits that the clamping arrangements and wedges in the Yalden declaration do not use a clamp bar with a transversely angled upper surface to engage the transversely angled lower surface of the wedge.  While the Yalden declaration may refer to wedges with two inclinations on their upper surfaces, there is no mention of wedges with transversely inclined lower surfaces.

The Polyscreen opposition

Mr. Wilson indicated by telephone at the hearing that Polyscreen had no submissions to make in relation to the proposed amended claims.

At the hearing, Mr. Turner briefly referred to the Kalbitzer declaration and submitted that the declaration does not make mention anywhere of wedges with lower inclined surfaces and clamp bars with upper inclined surfaces.

The Lettela opposition

Mr. Cowin made submissions on the specification as accepted.  He made the point that, as the proposed amendments were made available to Lettela only one week before the hearing, there had been insufficient time for a full consideration of the proposed new claims.  Nevertheless, he also made submissions in relation to these new claims.

In relation to section 40 of the 1952 Act, Mr. Cowin asserted that accepted claim 1 lacks clarity and fair basis because the wording "said reaction surface and said wedge surface extending longitudinally of said clamp bar and defining an acute angle with respect thereto" is ambiguous as to the direction of the angle.  It could be in either a longitudinal or transverse direction.  However there is no disclosure of the upper surface of the wedge being transversely angled in relation to the clamp bar.  A similar problem occurs in the wording of accepted claim 3.

Mr. Cowin submitted that the proposed new claims largely overcame this problem.

In relation to novelty, Mr. Cowin submitted that the test for novelty is the same as the test for infringement so that if the alleged instance of prior publication or use was put forward it would constitute an infringement of the claims under test. Each essential integer must be present for lack of novelty to be proved.

Mr. Cowin referred to the Bernadou, Woodgate and Smith declarations which refer to the Simonacco screening machine and submitted that the clamping arrangements and all modifications occurred before the earliest priority date of the claims as accepted. Consequently accepted claims 1 to 4 are fully anticipated.  The omnibus accepted claim 5 includes nothing that would constitute an essential difference.  The accepted specification does not highlight any additional notable feature.  Therefore claim 5 also is anticipated by the Simonacco screening machine.

Mr. Cowin makes the point that Messrs. Bernadou, Smith and Woodgate corroborate each other's evidence.

In referring to the applicant's declarants, Mr. Cowin points out that Messrs. Williams, Fox and Kelly may not have seen the modifications to the clamping arrangements because of the dirty nature of the machine in operation.  Also, Mr. Smith's job required him to remain operational on a day-to-day basis.  Thus he might make various minor modifications to the clamping arrangements without reporting to Messrs. Williams, Fox and Kelly.  His job did not require him to report to any of these employees.  Not everyone at Newdell was intimately aware of the changes being made to the Simonacco machine on an ongoing basis.

Mr. Cowin then referred to the Poole declaration and submitted that the Argyle machine would constitute an infringement of at least accepted claims 1 to 4.  Mr. Cowin pointed out that the Poole declaration has been unchallenged.  The McGregor declaration does not dispute what is actually shown in the engineering drawings.

In relation to the proposed amended claims, Mr. Cowin conceded that the Argyle machine does not provide a full anticipation.  However he maintained that the modified Simonacco machine anticipated all of the proposed amended claims.  While there was no specific disclosure of the Simonacco machine having wedges and clamp bars of the same width as in proposed amended claim 2, the various declarations and exhibits show that the wedges and clamp bars are of substantially the same width.  Mr. Cowin submitted that this particular dimension was an inessential integer and/or a mere mechanical equivalent.

In respect of obviousness, Mr. Cowin submitted that the modified Simonacco machine completely anticipates the claims as accepted.
In relation to the proposed amended claims, the modified Simonacco machine completely anticipates claim 1.  Claim 2 which refers to the dimension of the wedge and clamp bar does not include a feature which provides a level of inventiveness sufficient to sustain a valid patent.  Mr. Cowin pointed out that the specification as accepted makes no specific mention of this dimension.  It is only a feature of the illustrated support assembly.  There is no indication of why this dimension should provide an invention.  Similarly, the Z-shaped bracket defined in claim 3 as proposed to be amended does not rate a mention in the specification as accepted.  It again is only a feature of the illustrated support.  In any case this feature in the proposed amended claim 3 is also provided in the Simonacco machine.

In respect of the Argyle machine, Mr. Cowin submitted that, although Lettela conceded that the Argyle machine does not contain each and every feature of proposed new claim 1, the proposed new claims are obvious because they do no more than define modified wedges the properties of which are well known.

Mr. Turner indicated that his submissions would be in respect of the claims as proposed to be amended as the applicant intended to pursue these new claims only.

Mr. Turner then made submissions in relation to the various declarations provided by Lettela as part of its evidence-in-support and evidence-in-reply.

In relation to the first Bernadou declaration, Mr. Turner pointed out that Mr. Bernadou states that he was aware of the modifications to the Simonacco machine but does not state that he actually saw the modifications.  Mr. Turner further pointed out that the Bernadou declaration provides no drawings or hard evidence to support the allegation that modifications were made to the Simonacco machine nor are there any specific dates provided apart from a general reference to the 1985 to 1987 period.  Mr. Turner contrasted the documentary evidence provided in relation to the modified wedges provided by Mr. Bernadou's company with the lack of evidence provided in relation to the later modifications made to the Simonacco machine of which Mr. Bernadou states that he is aware.

In relation to the second Bernadou declaration,  Mr. Turner pointed out that there is no indication of when the modified slats were made and therefore they could have been made after the earliest priority date of the claims (as proposed to be amended).  Also no invoices or drawings have been provided in relation to these modified slats.  Mr. Turner contrasted this with the drawings and invoices provided in relation to the S 298 wedges provided by Mr. Bernadou's company.

With respect to the first Smith declaration, Mr. Turner queried the accuracy of the September 1987 date referred to in a number of paragraphs in the Smith declaration.  He submitted that no evidence had been lodged to substantiate this date which was close to the earliest priority date of the claims as proposed to be amended.

With respect to the second Smith declaration, Mr. Turner queried the role of Mr. Smith in relation to the modifying of the Simonacco machine.  Mr. Turner submitted that Mr. Smith does not state that he was in charge of modifying machines but only maintaining them nor does Mr. Smith state that he called for the modifications to be made.  Mr. Turner submitted that therefore one had to assume that the call for modifications had to have been made by somebody else.  Mr. Turner submitted that the modifications would either have originated from a superior or would have had to pass a superior for the commissioning and purchase of the relevant items required for the modification.

Mr. Turner briefly referred to the Woodgate declaration and pointed out that it too provides no specific dates (other than between late 1984 and 17 December 1987) when the modified slats referred to in the second Bernadou declaration  were made.

In relation to the Argyle machine, Mr. Turner submitted that this machine does not have a double-acting or double-taper wedge and thus it would only clamp in a single direction.

Mr. Turner then turned to the credibility of Lettela's declarants.  He submitted that both Mr. Bernadou and Mr. Woodgate are employees of Lettela and therefore have a vested interest in the opposition.  As a consequence of this, Mr. Turner asserted that their evidence should be discounted to a certain degree.  While Mr. Smith is not an employee of Lettela, Mr. Turner submitted that Mr. Smith has provided no hard evidence of the alleged modifications.

Mr. Turner then turned to the applicant's declarants and submitted that they were all independent experts who are not employed by the applicant.  Their evidence contradicts that provided by Lettela. According to Mr. Turner, Mr. Kelly is a leading hand and Mr. Williams was the engineer in charge.  If new equipment was installed to modify the Simonacco machine, one would expect the engineer in charge and the leading hand to know about it according to Mr. Turner.  However neither of them recalls any such modification at the relevant time.

On the subject of novelty, Mr. Turner submitted that the earlier modifications to the Simonacco machine clearly did not include all the essential integers of the claims as proposed to be amended.  Also there was no evidence to indicate what is a workshop improvement.

In relation to the later modifications to the Simonacco machine, Mr. Turner summarised the position as being the existence of one independent witness on one side (Mr. Smith) as compared with three independent witnesses on the other side.  The three independent witnesses provided by the applicant held different positions in the relevant company.  They provide specific details in the declarations as opposed to the Smith declaration where there is no supporting documentary evidence provided.

Mr. Cowin provided further submissions at the hearing in relation to Mr. Turner's comments.  He pointed out that the reason Mr. Smith referred to September 1987 in his declaration was that he had left the Newdell coal washery after that time.

In relation to the modified slats referred to in the second Bernadou declaration and the Woodgate declaration, Mr. Cowin submitted that there were no drawings made of the modified slat because the modification was so simple.

Mr. Cowin conceded that two of Lettela's declarants were employees of Lettela but this did not affect their evidence which was mainly factual in nature.

In relation to the applicant's evidence, Mr. Cowin submitted that the modifications were not major pieces of new equipment but were small consumable items which were discarded on a regular basis.  Consequently it was not surprising that the applicant's declarants were not aware of these modifications.

DECISION

These matters have been complicated by the relatively late filing of a statement of proposed amendments.  The opponents would not have each received a copy of the proposed amendments until at most a week before the hearing was held.  I note Mr. Cowin's comments referred to earlier in this respect.

Since all evidence served in relation to the three oppositions is directed at the claims as accepted, I believe that I should decide the three oppositions based on the claims as accepted.  As Mr. Cowin also made submissions at the hearing on the claims as proposed to be amended and Mr. Mischlewski and Mr. Wilson also made very brief submissions in relation to these claims, I will then consider what effect, if any, the proposed amendments might have on my findings in relation to the claims as accepted.

Section 40

I agree with Mr. Cowin that the wording "defining an acute angle with respect thereto" in claim 1 is ambiguous as to the direction of the angle.  As Mr. Cowin suggests, the angle could be either in the longitudinal or transverse direction of the clamp bar.  The ambiguity is exacerbated by the later wording in the claim that clamping takes place as a result of movement of the wedge member in a predetermined direction.  This predetermined direction could be along the longitudinal or transverse axis of the clamp bar.  There is a consequential ambiguity in claim 3 which is appended via claim 2 to claim 1.  The specification provides no descriptive support for a wedge member which has its upper (as opposed to its lower) surface acutely angled in the transverse direction of the clamp bar.  Therefore, I do not believe that claims 1 and 3 are fairly based on the matter described in the body of the specification.

I have found that claims 1 and 3 do not comply with section 40.

Novelty

As Mr. Turner submitted, the law in respect of novelty has been clarified by the relatively recent Federal Court decisions Werner & Co. v Bailey Aluminium 13 IPR 513 and Nicaro Holdings v Martin Engineering 16 IPR 545. In these decisions, the test for novelty is clearly indicated as being the reverse infringement test as set out by Aickin J in Meyers Taylor v Vicarr Industries (1977) CLR 228 as follows:

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

In Rodi Wienenberger AG v Henry Showell [1969] RPC 367 at page 391, infringement of a claim is said to occur when "each and every one of the essential integers" of that claim have been taken.

Thus in order to decide whether or not the claims lack novelty, I must determine whether or not each and every essential integer of the respective claim is disclosed in the earlier publication or use.

I note here that the claims have a priority date of 17 December 1987.  This has not been challenged.

The Richardson and Polyscreen oppositions

Before determining whether or not the systems referred to by Richardson and Polyscreen remove the novelty from the claims in suit, I have to decide whether or not the systems were used or published prior to the priority date of the claims.

Each of the Yalden and Kalbitzer declarations provides no supporting evidence as to the exact features of the wedging systems that Richardson and Polyscreen distributed prior to December 1987.  The two declarations include various assertions and exhibit various wedges, photographs and pamphlets illustrating wedging systems which are similar to the claimed support assembly.  However, although the two declarants allege that these systems were distributed and installed before December 1987, each declaration provides no corroborating evidence such as invoices etc. to establish when the wedges were made and distributed, when the photographed systems were installed or when the pamphlets were published.

I also note that Mr. Yalden and Mr. Kalbitzer are employees of Richardson and Polyscreen respectively.

However, the French declaration does provide support for the statements made in the Kalbitzer declaration.  I also note that Mr. French appears to be an independent witness and therefore I place great weight on his evidence.  Also the Yalden declaration provides some support for the statements made in the Kalbitzer declaration.  This together with the fact that the Richardson and Polyscreen evidence has been largely unchallenged by the applicant leads me to the conclusion that the screen assemblies and clamping arrangements referred to in the Yalden, Kalbitzer and French declarations were manufactured and used prior to the priority date of the present claims.

Therefore I am of the opinion that before the priority date of the claims in suit, Richardson, Polyscreen and Boral Melwire made and/or distributed screen panel support assemblies which included brackets, wedges, clamp bars and support bars whereby the sides of the square screen panels were sandwiched between the clamp bars and the support bars.  The wedges and brackets had mating upper wedge and reaction surfaces respectively which extended longitudinally of the clamp bar and formed a longitudinal acute angle with the clamp bar.  The wedges in some instances also had their upper wedge surfaces acutely angled in the transverse direction of the clamp bar.  When the wedges were moved in the longitudinal direction of the clamp bar, the clamp bar was forced into clamping engagement with the panel.  The wedges had lower force transmitting surfaces which abutted an upper force transmitting surface of the clamp bar and the lower surfaces lay within a plane which intersected at an acute angle a plane containing the upper wedge surface.

There is no indication that wedges were made or distributed which had an upper surface acutely angled in the longitudinal direction and a lower surface acutely angled in the transverse direction of the clamp bar nor is there any indication that the upper surface of the clamp bar was acutely angled in its transverse direction.

In comparing the above assemblies with the claimed assemblies, I believe that all the essential features, indeed all the features, of claims 1, 2, 3 and 4 have been taken by the assemblies made and/or distributed by Richardson, Polyscreen and Boral Melwire.  Therefore, I find claims 1 to 4 are not novel in the light of these previously used assemblies.

I have indicated that these earlier assemblies do not include the particular modification in which the lower surfaces of the wedges and the upper surface of the clamp bar are transversely angled.  Such an arrangement is shown in the drawings of the present specification.
Claim 5 is an omnibus claim.  To determine the scope of the claim and the nature of the essential features, I must consider the described invention and examine the drawings to discover how the essential integers are particularised in the drawings.

The described invention clearly has the same features as defined in claim 1 including wedges and clamp bars.  The particular wedges and clamp bar disclosed in the drawings to which claim 5 refers have the transversely acutely angled wedges and clamp bars.  Because wedges and clamp bars are essential to claim 5, I believe these types of wedges and clamp bars as particularised in the drawings are essential to claim 5.  Therefore all the essential features of claim 5 are not found in the earlier assemblies.  As a result, I cannot say that claim 5 is not novel in the light of this evidence.

I have found that claims 1 to 4 are not novel.

The Lettela opposition

In relation to the ground of lack of novelty, Lettela has relied on three instances of prior use.  For ease of reference, I will refer to them as the early Simonacco machine, the modified Simonacco machine and the Argyle machine.

The early Simonacco machine

It appears to me that this early Simonacco machine had the following features:

.   a screen panel;

.   support bars;

.   clamp bars;

.brackets each with a reaction surface extending in the longitudinal direction of the respective clamp bars but not defining an acute angle in the longitudinal direction of the respective clamp bars; and

.wedges with lower surfaces which contact the upper surface of the clamp bars and with upper surfaces which are acutely angled in two directions viz. in the longitudinal direction of the wedge and clamp bar and in the transverse direction of the wedge and clamp bar.

I have come to this conclusion because some of the assertions made by Lettela's declarants are supported at least in part by documentary evidence.  The S 298 drawing mentioned previously in relation to the evidence filed discloses the particular two‑angled wedge I have listed above and the dated invoices indicate that such wedges were distributed before the priority date of the present claims.  While I am conscious of the fact that the present claims are directed to a combination of features and not merely to a particular type of wedge, I nevertheless am prepared to accept the evidence of Mr. Smith and Mr. Bernadou that the other features I have listed above were also present in the early Simonacco machine before the priority date of the present claims.  I note also that this part of Lettela's evidence has not been challenged by the applicant and that the Bernadou declaration corroborates what has been said in the Smith declaration in relation to the early Simonacco machine.

The early Simonacco machine did not have clamp bars with transversely angled upper surfaces and corresponding transversely angled lower surfaces on the wedges.

I note that the early Simonacco machine did not have brackets with longitudinally acutely angled reaction surfaces.  Although the Bernadou declaration appears to indicate that the brackets were in fact longitudinally angled in the early Simonacco machine, this is in contradiction to paragraph 9 of the first Smith declaration which clearly indicates that the angled brackets were in fact a later modification of the early Simonacco machine.  As Mr. Smith was actually an employee at the Newdell washery, I favour his version of what features were initially present in the early Simonacco machine.

As I believe that the angled brackets are one of the essential features of the presently claimed assembly, I do not believe that any of the claims lack novelty in the light of the early Simonacco machine because not all of the essential features of the claims are found in the early Simonacco machine.

The modified Simonacco machine

The arguments made in relation to the modified Simonacco machine have raised a number of issues which I need to resolve.  They are as follows:

.   Where were the alleged modifications made?

.   Did the modifications take place at all?

.If the modifications did take place, were all the modifications present at any one time so that a combination of all the modified features existed?

The evidence by Lettela appears to suggest that some of the modifications were made on-site at the Newdell washery (or at least elsewhere than at Elastomers Australia) and some of the modifications were made by Elastomers Australia to parts which were then distributed to the Newdell washery.

I will summarise what I believe to be the alleged modifications as follows:

Modifications made on site

.The brackets were bent down so that the reaction surfaces were acutely angled in the longitudinal direction of the clamp bar.

.The brackets were modified to have a straightened Z shape in profile so that the additional leg helped to retain the wedge in place.

.The wedges were modified to have longitudinally angled upper surfaces and transversely angled lower surfaces.  While the Woodgate declaration indicates that the side slats were modified so that their upper surfaces were transversely angled to match the laterally sloped lower surfaces of the fixing wedges, there is no evidence before me to suggest that Elastomers Australia produced wedges with longitudinally angled upper surfaces and transversely angled lower surfaces.  Therefore I must assume that such modified wedges if they did exist were made on-site.

Modifications made by Elastomers Australia

.The side slats or clamp bars were modified by planing their upper surfaces to form transverse angles.

In considering whether or not the modifications to the Simonacco machine actually took place, I am faced with declarations by Messrs Smith, Bernadou and Woodgate on the one hand stating that the modifications took place and declarations by Messrs Fox, Williams and Kelly on the other hand stating that the modifications did not take place.

Graham J in Seiller's Application [1970] RPC 103 at page 106 said:

"In my judgement it is necessary that proof of prior user in opposition cases should be very clear.  Normally, in the absence of cross-examination, this will involve corroboration of a mere statement as to recollection in a declaration, particularly where the time interval involved is considerable.  Such corroboration is often best found in documents contemporary with the facts to be proved."

Of course, it is not possible, in all circumstances, to provide documentary evidence.  Corroboration may instead be possible by evidence provided by another witness.

The standard of proof required in disputes of this nature is the civil standard of proof viz. the balance of probabilities.

In the present case, I have come to the opinion that three of the modifications were made on-site at the Newdell washery.  Two of Lettela's witnesses, Mr. Bernadou and Mr. Woodgate, employees of Elastomers Australia, were not employed at Newdell and there is no evidence to suggest that they ever visited the Newdell washery.  Therefore, I do not place great weight on allegations made by them about modifications that were actually made at Newdell.  In this respect I note the comments made by Mr. Turner that the Bernadou declaration merely states that Mr. Bernadou was "aware" of the modifications.  I place more weight on the evidence provided by these two witnesses on what Elastomers Australia supplied to the Newdell washery as opposed to modifications made on-site at Newdell.

Therefore the modifications made on-site at the Newdell washery to which I have referred to above and which are detailed in the Smith declaration are largely uncorroborated.  There is no documentary supporting evidence provided and, as I indicated above, I have largely discounted the evidence in the Bernadou and Woodgate declarations in relation to the modifications made at Newdell.

It may be the case that if such modifications occurred on-site, they were of such a minor nature that employees other than those such as Mr. Smith with hands-on experience of the assemblies would not have known about them.  Nevertheless, as Mr. Turner has submitted, the three witnesses provided by the applicant held three different positions at Newdell which required the witnesses to be aware of the state of the Simonacco machines in some capacity or other.  Therefore, on the evidence before me, I believe that I am bound to decide that on the balance of probabilities the evidence provided by the three independent employees of Newdell, Mr. Fox, Mr. Williams and Mr. Kelly, is more likely to reflect what occurred in relation to the Simonacco machine than the substantially uncorroborated evidence of Mr. Smith.  Thus I must assume that no modifications were made to the Simonacco machine on-site.

With respect to the alleged modifications made by Elastomers Australia, the evidence provided by Mr. Bernadou and Mr. Woodgate is somewhat confusing.  Both the second Bernadou declaration and the Woodgate declaration indicate that Elastomers Australia manufactured side slats or clamp bars with transversely angled upper surfaces to match the laterally sloped surfaces of the wedges produced by the company as shown in drawing S 298 to which I have referred earlier.  However the wedges depicted in the S 298 drawing have longitudinally and laterally angled upper surfaces.  The lower surfaces of these wedges are not angled at all.

Further, in relation to the modified side slats, I note that no invoices or purchase orders have been provided.  This is to be compared with the invoices and purchase orders provided in relation to the wedges depicted in S 298.

On the whole, I believe that, although such modified side slats or clamp bars may have been made by Elastomers Australia, there is no documentary corroboration that those side slats were actually received at Newdell.

While the Smith declaration makes the allegation that such modified side slats were used at Newdell, the evidence provided by Mr. Fox, Mr. Williams and Mr. Kelly disputes this.  As the modified parts were not made on site, they would have had to pass through the normal receipting procedures for goods arriving at Newdell.  Consequently, on the balance of probabilities, I believe that, had these modified side slats been received at Newdell, they would have been at least seen by at least one of the three witnesses provided by the applicant.  Therefore, I believe that I am bound to accept the evidence provided by Mr. Fox, Mr. Williams and Mr. Kelly that such modified slats were not used on the Simonacco machine.

Consequently, I believe that there is not sufficient evidence before me to allow me to come to the conclusion that modifications were made to the Simonacco machine of the type that I have itemised above.

I would add that, even if I had found that all the alleged modifications had been made to the Simonacco machine, there is certainly no evidence to suggest that a Simonacco machine existed with all the modifications made to it at any one particular time.

The Argyle machine

The Poole declaration exhibits an engineering drawing which discloses a chute with a screen assembly and fastening means.  The drawing is annotated as being drawn in 1984.  Although a number of annotations also include dates in 1988 and 1990, as Mr. Poole indicates in his declaration, the drawing has been stamped with the words "as constructed drawing" and that stamp imprint is dated 28 November 1985.

Mr. Poole indicates in his declaration that 5 assemblies were installed during 1985 and commissioned in late 1985 and freely available for public inspection since commissioning in 1985.

The applicant has not challenged the evidence provided in the Poole declaration.

Therefore, as the evidence in the Poole declaration is corroborated in part by the engineering drawing, I believe that on the balance of probabilities the assemblies depicted in the engineering drawing were available to the public before the priority date of the present claims.

I have referred to the features of the Argyle machine earlier in relation to the evidence which has been filed.  I consider that the Argyle machine includes all the essential integers of claims 1 to 4 and therefore claims 1 to 4 lack novelty.  I do not believe that the Argyle machine includes all the essential integers of claim 5 , the omnibus claim, because it does not disclose the combination of a wedge with a transversely angled lower surface and a clamp bar with a corresponding transversely angled upper surface.  Therefore claim 5 cannot be said to lack novelty in the light of the Argyle machine.

I have found that claims 1 to 4 are not novel.

Obviousness

I note that the 1952 Act applies to these oppositions and therefore the law on obviousness is the law in relation to obviousness under the 1952 Act.

Therefore, I note the remarks of Aickin J. in Wellcome Foundation Limited v VR Laboratories (Aust.) Pty. Ltd. (1982) RPC 343 at 346:

"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 only evidence relating to what was common general knowledge in the art before the priority date occurs in the Kalbitzer and French declarations filed as part of the Polyscreen opposition.  Both declarants submit that screen assemblies including support bars, clamp bars and wedges with upper surfaces and brackets with reaction surfaces being longitudinally acutely angled were part of the common general knowledge in the art before the priority date of the present claims.

Mr. Kalbitzer indicates that he became manager of Polyscreen in 1987 and for the last fifteen years at the company has specialised in screening equipment for the mining industry.  I believe that he could be considered as a person skilled in the art of screening assembly manufacture.

Mr. French is a distributor rather than a manufacturer of screening assemblies and therefore cannot necessarily be considered to be a person skilled in the art.

However, Mr. Yalden who is employed by another company (Richardson) which manufactures screening equipment for the mining industry also indicates that he was aware of the screening assemblies referred to by Mr. Kalbitzer before the priority date of the claims.  While Mr. Yalden does not allege that this type of assembly was part of the common general knowledge in the art, his evidence nevertheless does provide some support for the allegations of Mr. Kalbitzer about the state of the common general knowledge in the art at that time.

In the absence of any argument to the contrary from the applicant, I am prepared to accept that the assemblies referred to in the Kalbitzer declaration were in fact part of the common general knowledge before the priority date of the claims in suit.

Therefore, I find that claims 1 to 4 are obvious in the light of the common general knowledge as the same combination of features was part of the common general knowledge in the art before the priority date of the present claims.  I do not believe that claim 5 is obvious because it includes features which are not part of the common general knowledge.

I do not agree with Mr. Cowin's arguments on behalf of Lettela in relation to obviousness.  Lettela has provided no evidence as to what is part of the common general knowledge in relation to screen assemblies.  Therefore there is nothing before me to indicate what might be workshop improvements or what might be the well known properties of wedges.

I have found that claims 1 to 4 are obvious.

Effect of the proposed amendments

On even a cursory look at the claims as proposed to be amended, it is clear to me that the proposed amendments would not be allowable were they to proceed as presently worded through the normal examination process.

I am of the opinion that the proposed amendments would not be allowable on at least three fronts.

Firstly, as a result of the proposed amendments, the specification would claim matter not is substance disclosed in the specification as filed and thus would contravene section 102(1) of the 1990 Act.  This is because there is no support in the specification as filed for the feature defined in proposed claim 1 of at least one (bracket) corresponding to each wedge.  The specification as filed clearly envisages one bracket only for each wedge.

Secondly, as a result of the proposed amendments, the claims would not in substance fall within the scope of the claims of the specification before amendment.  All of the claims before amendment clearly define the reaction surfaces of the brackets (or wedge means) as extending longitudinally and defining an acute angle with respect to the clamp bars.  This is clearly an essential integer of these claims.  However proposed claims 1 and 2 do not define this feature at all and therefore no longer in substance fall within the scope of the claims before amendment.  Consequently, the proposed amendments would not be allowable under section 102(2)(a).

Thirdly, I note that there have not been proposed changes to the body of the specification to bring it into line with the content of the proposed new claims.  Consequently, the proposed new claims would contravene section 40 of the 1990 Act as they are inconsistent with the invention described.  As a result, the proposed amendments would not be allowable under section 102(2)(b)

There may well be other reasons why the proposed amendments are not allowable but, as I have mentioned, after even a cursory look at the proposed new claims, I have found three reasons why the proposed amendments are not allowable under section 102 of the 1990 Act.  Consequently I do not believe that it is necessary for me to consider what effect the proposed claims might have on my findings in relation to the grounds of lack of novelty, obviousness and lack of compliance with section 40.

CONCLUSION

I have found that the Richardson opposition has been successful in relation to the ground of lack of novelty in that claims 1 to 4 are not novel.

I have found that the Polyscreen opposition has been successful in relation to the grounds of lack of novelty and obviousness in that claims 1 to 4 are not novel and are obvious.

I have found that the Lettela opposition has been successful in relation to the grounds of non-compliance with section 40 and lack of novelty in that claims 1 and 3 do not comply with section 40 and claims 1 to 4 are not novel.

I have also found that the proposed amendments are not allowable.

As I found that the oppositions were unsuccessful in relation to claim 5 and therefore it may be possible to overcome the above deficiencies to claims 1 to 4, I will allow the applicant an opportunity to propose further amendments to the specification to overcome the deficiencies within 60 days from the date of this decision.

COSTS

As all three opponents have been successful in their oppositions, I award costs up to and including the hearing against the applicant.

R.W. HALLETT

Delegate of the Commissioner of Patents

Patent attorneys for the applicant  :  Spruson & Ferguson, Sydney

Patent attorneys for Richardson     :  Watermark, Melbourne

Patent attorneys for Lettela:  Phillips Ormonde &     Fitzpatrick, Melbourne

Patent attorneys for Polyscreen     :  Griffith Hack & Co, Melbourne