CSR Building Products Limited v United States Gypsum Company
[2015] APO 21
•20 May 2015
IP AUSTRALIA
AUSTRALIAN PATENT OFFICE
CSR Building Products Limited v United States Gypsum Company [2015] APO 21
Patent Application: 2007302768
Title:Composite light weight gypsum board
Patent Applicant: United States Gypsum Company
Opponent: CSR Building Products Limited
Delegate: Rhys Munzel
Decision Date: 20 May 2015
Hearing Date: 25 February 2015, in Canberra
Catchwords: PATENTS – composite gypsum board – novelty – inventive step – fair basis – sufficiency – utility – fair basis made out – claims are wider than and travel beyond the matter described – utility made out – claims define gypsum boards which do not meet the invention’s promise of high or sufficient strength – opposition successful
Representation: Patent applicant: Ed Heerey, of counsel, instructed by Gus Hazel and Andrew Scott of James & Wells
Opponent: Neil Murray, of counsel, instructed by Derek Baigent, Robert Wulff and Samantha Keirs of Griffith Hack
IP AUSTRALIA
AUSTRALIAN PATENT OFFICE
Patent Application: 2007302768
Title:Composite light weight gypsum board
Patent Applicant: United States Gypsum Company
Date of Decision: 20 May 2015
DECISION
The opposition succeeds on the grounds that:
·claims 1-21 are not fairly based; and
·claims 1-21 lack utility;
I allow the United States Gypsum Company eight weeks from the date of this decision to propose amendments to overcome these deficiencies.
I award costs according to Schedule 8 against United States Gypsum Company.
REASONS FOR DECISION
Background
Patent application 2007302768 (“the application”) in the name of United States Gypsum Company (“USG”) was examined and accepted by the Commissioner, and subsequently opposed by CSR Building Products Limited (“CSR”).
CSR and USG each rely on expert evidence in the form of declarations. CSR’s evidence in support consists of declarations by:
· Glen Gordon dated 18 April 2013 (“Gordon 1”), with Exhibits GHG1 – GHG26;
· Gregory Neil dated 20 May 2013 (“Neil 1”), with Exhibits GJN1-GJN6; and
· Bob Bruce dated 26 May 2013 (“Bruce 1”), with Exhibit BB1.
USG’s evidence in answer consists of declarations by:
· Qingxia Liu dated 29 September 2013 (“Liu 1”), with Exhibits QL1-QL4;
· William White (“White 1”) dated 30 September 2013, with Exhibits WW1-WW11; and
· Timothy Ball (“Ball 1”) dated 1 October 2013, with Exhibit KB1.
CSR’s evidence in reply consists of declarations by:
· Bob Bruce dated 17 December 2013 (“Bruce 2”) with Exhibits BB2-BB7 and BB9; and
· Gregory Neil dated 19 December 2013 (“Neil 2”), together with Exhibit GJN7.
When filing its evidence in reply CSR filed further evidence consisting of Exhibits GJN8-GJN10, BB8 and BB10. USG then filed further evidence in response consisting of declarations by:
· Qingxia Liu dated 19 June 2014 (“Liu 2”), with Exhibit QL1;
· William White dated 19 June 2014 (“White 2”);
· Timothy Ball dated 20 June 2014 (“Ball 2”); and
· Corey Gatt dated 20 June 2014 (“Gatt 1”), together with Annexure A.
The hearing occurred on 25 and 26 February 2015. Neil Murray, of counsel, instructed by Derek Baigent, Robert Wulff and Samantha Keirs of Griffith Hack attended on behalf of CSR. Ed Heerey, of counsel, instructed by Gus Hazel and Andrew Scott of James & Wells attended on behalf of USG.
Onus
The examination request for the application was filed on 4 October 2010. As a consequence, substantive amendments of the Patents Act[1] brought about by the Intellectual Property Laws Amendment (Raising the Bar) Act[2] do not apply to this opposition. This includes the amendment to s 60(3A) that allows the Commissioner to refuse a patent application if satisfied on the balance of probabilities that a ground of opposition exists. Instead, CSR must establish that it is clear that a valid patent cannot be granted.[3]
[1] 1990 (Cth) (“the Act”).
[2] 2012 (Cth).
[3] F Hoffman La Roche AG v New England Biolabs Inc [2000] FCA 283, [29], [67]; [2000] FCA 283; 50 IPR 305, 311, 319; Commissioner of Patents v Sherman [2008] FCAFC 182, [18], [22]; [2008] FCAFC 182; 79 IPR 426; Genetics Institute Inc v Kirin-Amgen Inc [1999] FCA 742; [1999] 92 FCR 106, [17].
In Austal Ships Pty Ltd v Stena Rederi Aktiebolag,[4] Bennett J observed:
“I can accept that a lower standard may apply to proof of evidence such as whether a document has been published or, indeed, whether a prior art vessel was well-known. I do not accept that it properly applies to the factual question that itself is the test for obviousness or lack of inventive step. Where the factual question is itself the legal test, as set out in s 7(3) of the Act, it seems to me that it should be determined at the higher standard. That means that where there are two opposing expert views that are conclusive on obviousness, both presented bona fide by witnesses of accepted expertise, unless one set of views can be rejected on proper grounds, the legal burden to establish a ground of opposition is not discharged; the Court cannot be practically certain that obviousness or lack of inventive step is established.”
[4] 66 IPR 420, 423; [2005] FCA 805, [12].
Grounds of opposition
CSR relies on the following grounds of opposition:
- lack of fair basis;
- lack of sufficiency;
- lacks of utility;
- lack of novelty; and
- lack of an inventive step.
Field of the invention
Paragraph [0001] of the specification as currently filed (“the specification”) provides the field of the invention and relates it to light weight composite gypsum boards having high strength, and to a method of making such boards using a gypsum containing slurry to form a foamed low density set gypsum core and non-foamed (or reduced-foamed) bonding high density layers that bond the top and bottom cover sheets to the core.
The person skilled in the art
The person skilled in the art (“the PSA”) is the hypothetical person to whom the patent specification is addressed.[5] The identity of the PSA will vary with the nature of the invention and the field with which it is concerned.[6] In KD Kanopy Australasia Pty Ltd v InstaImage Pty Ltd,[7] Kiefel J identified the PSA as:
“a person acquainted with the surrounding circumstances of the state of the art and manufacture at the relevant time…. They are likely to have a ‘practical interest in the subject matter of the invention’… and may often work in the art with which the invention is connected.”
[5] General Tire & Rubber Co. v Firestone Tyre & Rubber Co. Ltd (1971) 1A IPR 121, 134
[6] Aktiebolaget Hassle v Alphapharm Pty Ltd (2002) 212 CLR 411, 465 [152]-[153]; Ranbaxy Australia Pty Ltd v Warner-Lambert Co LLC (No 2) (2006) 71 IPR 46, 63[67].
[7] (2007) 71 IPR 615, 621.
CSR submits the PSA is “a person who is knowledgeable about techniques for manufacturing and testing gypsum boards… and is a person who is aware of industry developments.”[8] USG observe that CSR identifies the PSA by what he or she knows, rather than the role he or she would have. USG submit the PSA ought to be identified by their role. I prefer USG’s approach. USG submits that the PSA is a team consisting of a foreman and/or a trained laboratory technician working in gypsum board manufacture. I agree these people have a practical interest in the subject matter of the invention.
[8] CSR’s summary of written submissions, [11].
Mr Gatt notes there are generally two types of foremen.[9] The first has usually gained experience as an operator “from the floor” and would typically have no formal qualifications.[10] The second usually has an academic qualification, the intent being to “manage them up through the ranks.”[11] Mr Gatt notes that foremen would have had limited exposure to other manufacturing plants, and would not have: been sent to conferences, read industry magazines, or been trained on advanced scientific or engineering topics.[12]
[9] Gatt 1, [12].
[10] Ibid.
[11] Ibid.
[12] Ibid, [13].
Each party relies on experts with significantly higher qualifications than a foreman or laboratory technician. The experts range from: technical consultants; technical or manufacturing managers; a professor; and the vice-president of an advanced technology group.[13] Dr Bruce completed two years of post-doctorate research before commencing as a “research scientist” in gypsum board manufacturing in 1967.[14] Professor Liu completed two PhDs before commencing as a “senior researcher” in gypsum products in 1998.[15] Professor Liu later led two teams respectively comprising four and five “PhDs” to develop new gypsum board technologies.[16] Mr White, while director of a process laboratory, was responsible for gypsum products research where he managed over 50 scientists and engineers.[17]
[13] Bruce 1, [1]; Neil 1, [1]; Gatt 1, [8]; Liu 1, [1]; White 1, [1].
[14] BB-1.
[15] QL-1.
[16] Ibid.
[17] WW-1.
The gypsum board industry is described as “a very competitive international industry that is dominated by a relatively small number of large and sophisticated companies.”[18] There is also clear evidence, as set out above, that these companies employed or contracted scientists and engineers to conduct research into developing new gypsum board products. I include a scientist or engineer working in gypsum board research within the team.
[18] Bruce 2, [8].
Construing the claims
The correct approach to claim construction was discussed by Bennett J in H Lundbeck A/S v Alphapharm Pty Ltd:[19]
“Words in a claim should be read through the eyes of the skilled addressee in the context in which they appear. Words used in a specification are to be given the meaning which the person skilled in the art would attach to them, having regard to his or her own general knowledge and to what is disclosed in the body of the specification … while the claims define the monopoly claimed in the words of the patentee's choosing, the specification should be read as a whole … it is not permissible to read into a claim an additional integer or limitation to vary or qualify the claim by reference to the body of the specification … terms in the claim which are unclear may be defined or clarified by reference to the body of the specification.”
[19] [2009] FCAFC 70, 81; IPR 228, [118]-[120].
The specification ends with 23 claims. Claims 1-3 and 15-17 are independent while claims 22 and 23 rely on references to the description. Claims 1-3 each commence as follows:
“A composite gypsum board comprising:
a set gypsum core having a dry density;
the set gypsum core adjacent to a first bonding layer having a dry density, the set gypsum core dry density being less than the first bonding layer dry density by a differential of at least about 10 pcf (about 160 kg/m3);
the first bonding layer having a thickness of about 2 mils (about 0.05 mm) to less than about 7 mils (about 0.2 mm);
the board having a dry density of about 35 pcf (about 560 kg/m3) or less; and”Claims 15-17 also share a common beginning, as follows:
“A method of making a composite gypsum board, the method comprising:
(a) mixing at least water and stucco, and optionally foam, to form a first slurry;
(b) depositing a portion of the first slurry of (a) on a first cover sheet to form a first bonding layer having a thickness of about 2 mils (about 0.05 mm) to less than about 7 mils (about 0.2 mm);
(c) adding foam to at least a portion of the first slurry of (a) and mixing to form a second slurry, wherein the second slurry comprises a greater amount of foam than the first slurry and has a lower wet density than the first slurry;
(d) depositing the second slurry of (c) onto the first bonding layer to form a panel;
(e) cutting the panel into a board of predetermined dimensions; and
(f) drying the board;
wherein
a set gypsum core is formed from the second slurry of (c) and has a dry density less than the first bonding layer dry density by a differential of at least about 10 pcf (about 160 kg/m3);the board has a dry density of about 35 pcf (about 560 kg/m3) or less; and”
These claims then end as set out in the following table:
Claims feature 1, 15 the set gypsum core has an average core hardness of at least about 11 pounds (about 5 kg) as determined in accordance with ASTM C473. 2, 16 the board has a ratio of dry density (pcf) to average core hardness (lb) of less than about 3.2, wherein the core hardness is determined in accordance with ASTM C473. 3, 17 the board, when at a thickness of about ½ inch (about 1.3 cm), has a nail pull resistance to average core hardness ratio from about 4 to about 8, each as determined in accordance with ASTM C473. What does having a dry density mean?
Professor Liu construed “having a dry density” as requiring the first bonding layer to have a constant density.[20] This construction cannot be applied consistently across the claims, as the overall board – comprising the set gypsum core and the first bonding layer – is also defined to have a dry density. I construe “having a dry density” as: having an overall density when dry.
[20] Liu 2, [39].
What is a “composite gypsum board”?
“Composite gypsum board” has a special meaning in the art relating to “a gypsum board with thin, high density, skins at the face and back of the board, separated by a foamed lower density gypsum core, having of [sic] large spherical voids within it.”[21] The claims utilise the term in a broader sense, which provides for a first high density bonding layer, or “skin”, while a second bonding layer is preferred but optional.[22]
[21] Neil 1, [18].
[22] as provided for in claim 7 of the specification.
Professor Liu’s trial boards
Two questions of construction arose from experiments performed by Professor Liu. Professor Liu set out to make composite gypsum boards according to the present invention.[23] He performed density analyses on the resulting boards to confirm that each had a bonding layer of the requisite thickness.[24] The analyses indicated a region, passing from the bonding layer to the core, where the density “dipped” to a minimum.
[23] Liu 1, [26].
[24] Ibid, [41].
Professor Liu provided the following explanations for the region:
“[o]ne of ordinary skill would appreciate that when the slurries contact and interface with one another there would be a transition zone, since the two slurries are of different densities.”[25]
and:
“The dip present in some of the profiles is due to the profiler detecting the presence of an air void at the interface of the bonding layer and core.”[26]
[25] Liu 2, [38].
[26] Liu 1, [44].
Dr Bruce elaborated on Professor Liu’s second explanation:
“There will be a reduction in the density of the gypsum at the interface between the bonding layer and the core gypsum. This is as a result of sheer stresses that arise along that interface during manufacturing. In general terms, sheer stresses at the interface break down the small foam bubbles which in turn leads to the creation of large voids and a thin plane of lower density gypsum.”[27]
[27] Bruce 2, [58].
The two questions of construction arising are:
(a)if there is a region of transitioning density between bonding layer and the core, where does the bonding layer end?
(b)does the term “adjacent” allow for a separate transition region between the bonding layer and the core?
Where does the bonding layer end?
Professor Liu originally identified the end of the bonding layer as the point where the density of the board has increased by 10 pcf over the average density of the core.[28] This selection arbitrarily relates the bonding layer to a particular result necessary to the claims instead of considering how the PSA would otherwise routinely or objectively identify the end of the bonding layer.
[28] Liu 1, [48].
Dr Bruce proposed that the interface is located at the bottom of the dip in density, i.e. the point of lowest density in the thin plane.[29] Applying this construction he proposes the bonding layers provided in the trial boards are at least 15 mils thick, which is significantly thicker than allowed by the claims.[30] He then proposes that the skilled person would be unable to manufacture a composite board having the defined bonding layer thickness.[31] I am also concerned with Dr Bruce’s approach. It is inconsistent with his earlier statement that:
“The thickness of the bonding layers as defined in the independent claims as between about 2 mils (thousandth of an inch) to about 7 mils is also standard for wallboard.”[32]
[29] Bruce 2, [58], [67].
[30] Ibid, [65].
[31] Ibid, [70]-[73].
[32] Bruce 1, at [6].
In response to Dr Bruce, Professor Liu suggests that, since the bonding layer “has a dry density” – which he construes to mean a constant density[33] – the end of the bonding layer must be found where the density is no longer constant.[34] I have set out above why I disagree with this.
[33] Liu 2, [39].
[34] Ibid, [40].
Whether any of the thin plane forms part of the bonding layer would, to my mind, depend on how the thin plane is formed. Dr Bruce describes the thin plane being formed by sheer stresses at the interface breaking down small foam bubbles which in turn creates large voids.[35] Since, it seems to me, these small foam bubbles are found in the foamed core and not typically in the non-foamed (or reduced foamed) bonding layer it follows that the large voids would form on the core side of the interface. Therefore, the interface would be found on the bonding layer side of the thin plane, and not in the middle of it.
[35] Bruce 2, [58].
As a further point, as I discuss below, the specification teaches that high density bonding layers are provided to overcome bonding issues caused by voids in the foamed core.[36] As bonding layers are provided to overcome issues caused by voids, it seems counter-intuitive to me to view a region of large voids – or part thereof – as part of a high density bonding layer.
Does the term “adjacent” allow for a transition region between the core and the bonding layer?
[36] The specification, [0013].
The specification teaches that the bonding layer is applied directly to the core[37] and there is no explicit instruction to provide an intermediate layer between the two. Nevertheless, both Professor Liu and Dr Bruce understand that a region of transitioning density will naturally form at the interface.[38] This region can be seen as either a distinct region; or as part of the core (as I set out above). In either case, any purposive construction must allow for it as the PSA understands it is provided.
[37] Ibid.
[38] Liu 1, [44]; Bruce 2, [58].
Fair basis and priority dates
CSR submits that claims 1-23 lack fair basis and are not entitled to the application’s earliest claimed priority date. The application claims priority from US 11/537395 (“the priority document”), filed on 29 September 2006. CSR submits that the priority date of the claims should be deferred to 25 July 2012, when pre-acceptance amendments were filed.
The priority date of any claim is determined under principles set out in the Act[39] and the Patents Regulations.[40] Most relevantly for the present opposition, a claim may derive priority from the date of filing of a specification which first discloses matter upon which the claim is fairly based.[41] In respect of the present application that may be either:
- the filing date of the priority document (29 September 2006);[42]
- the filing date of the application (29 August 2007);[43] or
·the filing date of the pre-acceptance amendments (25 July 2012).[44]
[39] 1990 (Cth), s 43(3).
[40] 1990 (Cth), rr 3.12-3.14.
[41] In RGC Mineral Sands Pty Ltd v Wimmera Industrial Minerals Pty Ltd (1998) 89 FCR 458, 460 Burchett J noted that the requirement of “in substance disclosed” is virtually the same as “fairly based”.
[42] Patents Regulations 1990 (Cth), r 3.12(1)(b).
[43] Ibid, r 3.12(1)(a).
[44] Ibid, r 3.14(b)
Legal tests
In considering fair basis, the High Court in Lockwood Security Products Pty Ltd v Doric Products Pty Ltd[45] approved the words of Gummow J in Rehm Pty Ltd v Websters Security System (International) Pty Ltd: [46]
“the question is whether there is a real and reasonably clear disclosure in the body of the specification of what is then claimed, so that the alleged invention as claimed is broadly, that is to say in a general sense, described in the body of the specification.”
[45] [2004] HCA 58, [69]; 217 CLR 274, 300 (“Lockwood v Doric”).
[46] (1988) 81 ALR 79, 95.
Lockwood v Doric[47] clarifies that the comparison required involves:
“construction of the specification as a whole, putting aside particular parts which, although in isolation they might appear to point against the ‘real’ disclosure, are in truth only loose or stray remarks.”
[47] [2004] HCA 58, [69]; 217 CLR 274.
USG noted the lingering relevance of the “Mond-Nickel Rules”[48] as a guide when considering fair basis. In explaining the Mond-Nickel Rules, USG referred to a passage of Leonardisv Sartas (No 1) Pty Ltd[49] (USG’s emphasis):
“The very terms of the well known tests stated in Re Mond Nickel Co Ltd's Application [1956] RPC 189 at 194, and particularly the first and second of those tests, imply that a claim need not take all of what is disclosed in the provisional specification. The first test asks "whether the alleged invention as claimed can be said to have been broadly described in the provisional specification", and the second then asks: "Is there anything in the provisional specification which is inconsistent with the alleged invention as claimed?" This plainly leaves open that there may be other material disclosed in the provisional specification, but not included in the claim, which, however, will destroy the fair basing of the claim only if it is ‘inconsistent with the alleged invention as claimed’.”
[48] Re Mond Nickel Company Ltd's Application [1956] RPC 189, 194.
[49] Leonardis (1996) 67 FCR 126, 144C-D.
This passage should be understood in light of Lockwood v Doric,[50] which clearly anticipates that a claim may lack fair basis where its scope is found to be broader than what is described in the specification. As discussed in Lockwood v Doric,[51] this occurred in Olin Corporation v Super Cartridge Co Pty Ltd[52] where claims to a shotgun cartridge case were found to lack fair basis because they omitted a step during production in which plastic forming the case was compressively deformed. I understand Leonardis[53] as setting out that certain material (for example features described as optional or relating to a different invention) need not be taken into a claim while “other material” (such as features clearly disclosed as forming a necessary part of the invention) may be required, for the sake of consistency, to be included in a claim. In Atlantis Corporation Pty Ltd v Schindler,[54] both judgments referred to Leonardis and then found the relevant claims to lack fair basis because they were, in Lockhart J’s words, “wider” than the matter disclosed.
[50] [2004] HCA 58 at [99]-[100]; 217 CLR 274.
[51] [2004] HCA 58, [98]; 217 CLR 274.
[52] [1977] HCA 23; (1994) 180 CLR 236.
[53] (1996) 67 FCR 126.
[54] [1997] FCA 1105; (1997) 39 IPR 29
Internal fair basis
I will begin by considering internal fair basis. This requires a comparison of the claims and the body of the specification.[55]
What is really and reasonably clearly disclosed in the body of the specification?
[55] Lockwood v Doric [2004] HCA 58, [49]; 217 CLR 274.
I repeat that paragraph [0001] relates the invention to light weight composite gypsum boards having high strength, and to a method of making such boards using a gypsum containing slurry to form a foamed low density set gypsum core and non-foamed (or reduced-foamed) bonding high density layers that bond the top and bottom cover sheets to the core. I also repeat that “composite gypsum boards” are generally understood as “a gypsum board with thin, high density, skins at the face and back of the board, separated by a foamed lower density gypsum core, having of large spherical voids within it.” [56]
[56] Neil 1, [18].
Paragraphs [0002]-[0006] describe the background to the invention. Gypsum is popularly used to make building products such as wallboard.[57] Gypsum wallboard is produced by mixing gypsum in its hemihydrate form (“stucco”) with water to form a slurry that is formed, shaped and dried.[58] Paragraphs [0003] and [0004] describe slurry additives. Pre-gelatinised starch increases the flexural and compressive strength of the resulting gypsum product.[59] Naphthalenesulphonate dispersants overcome slurry flow-ability problems arising from use of the pre-gelatinised starch.[60] Paragraph [0004] also refers to improvements allegedly discovered by the present inventors:
· naphthalenesulphonate dispersants, when used in sufficiently high amounts, cross-link to the pre-gelatinised starch to bind gypsum crystals together after drying. This improves the dry strength of the resulting gypsum composite; and
· trimetaphosphate salts, when used at previously unknown levels and in the presence of a specific dispersant, will improve slurry flow-ability even where high starch levels are present.
[57] The specification, [0002].
[58] Ibid, [0002]-[0004].
[59] Ibid, [0003].
[60] Ibid, [0004].
Paragraphs [0005] and [0006] discuss the characteristics of conventional gypsum wallboards. Conventional wallboards have adequate strength and meet the standards for nail pull resistance (77lb) and core hardness (11lb), but they are heavy and typically weigh up to 1600lb/MSF.[61] Paragraph [0005] states:
“If a way could be found to produce a high strength gypsum wallboard in which board weight (and density) is significantly reduced, without adversely affecting nail pull and hardness characteristics, this would represent a useful contribution to the art.”
[61] Ibid, [0005].
Paragraph [0006] notes that bonding layers are known to promote adherence or bonding of the paper cover sheets to the set gypsum core. However, these bonding layers are relatively thick, ranging from 7-50 mils. Use of these thick bonding layers can decrease the core hardness of the finished wallboard. Dry densities in these thick bonding layers range from 70-90 pcf. Paragraph [0006] notes that thinner bonding layers would be expected to be more difficult to apply and to present other difficulties. Paragraph [0006] concludes by stating:
“If a way could be found to make a low density set gypsum board using thinner, lighter bonding layers, without sacrificing core hardness or other important board properties, this would represent a useful contribution to the art.”
I find the field of the invention and the background to the invention to forecast that the invention to be disclosed will relate to making a reduced weight composite gypsum board product with thinner, lighter bonding layers while retaining strength properties.
Paragraphs [0007]-[0008s] are found under the heading “brief summary of the invention”, and reproduce verbatim the present claim set as “aspects” of the invention. I have discussed the invention claimed above and, for brevity, will not reproduce that discussion.
The “detailed description of the invention” begins at paragraph [0009]. Paragraph [0009] relevantly states:
“It has now unexpectedly been found that the preparation of a foamed low density set gypsum core using thinner, lighter top and bottom non-foamed (or reduced foamed) bonding high density layers to attain good bonding of a heavy top (face) cover sheet and a bottom (back) cover sheet, can provide a composite gypsum board having nail pull resistance, core hardness, and board strength.”
Paragraph [0009] directs the reader to an identified benefit of the invention: a composite gypsum board formed of a foamed low density core and thinner, lighter top and bottom non-foamed (or reduced-foamed) high density layers bonding the top and bottom cover sheets can surprisingly provide the requisite strength properties.
Paragraph [0010] then states:
“The composite gypsum board of the present invention includes a foamed low density set gypsum core having a top surface and a bottom surface, a top non-foamed (or reduced-foamed) bonding high density layer covering the top surface of the foamed low density set gypsum core, a top (or face) cover sheet having a foamed low density set gypsum core-facing surface, the top cover sheet bonded to the foamed low density set gypsum core by the top non-foamed (or reduced-foamed) bonding high density layer, a bottom non-foamed (or reduced-foamed) bonding high density layer covering the bottom surface of the foamed low density set gypsum core, and a bottom (or back) cover sheet having a foamed low density set gypsum core-facing surface, the bottom cover sheet bonded to the foamed low density set gypsum core by the bottom non-foamed (or reduced-foamed) bonding high density layer. Preferably the top cover sheet will be paper having a weight of about 60 lb/MSF (thickness about 18 mils). Additionally, the top (face) cover sheet and bottom (back) cover sheet are substantially parallel with respect to the foamed low density set gypsum core. The foamed low density set gypsum core is made from a foamed gypsum slurry containing stucco, and includes pregelatinised starch, and preferably a naphthalenesulfonate dispersant, and also preferably, sodium trimetaphosphate. The top and bottom non-foamed (or reduced-foamed) bonding high density layers can comprise from about 10% to about 16% of the of the [sic] total amount of gypsum slurry.”
The invention described in paragraph [0010] most notably includes:
· a foamed low density set gypsum core made from a foamed gypsum slurry containing stucco, and pregelatinised starch;
· top and bottom non-foamed (or reduced-foamed) high density bonding layers; and
· top and bottom cover sheets.
It also describes a number of additional features, such as use of a naphthalenesulfonate dispersant, as preferable or optional parts of the invention.
Paragraph [0011] then begins by stating:
“[a]ccording to one embodiment of the present invention, there are provided finished composite gypsum board [sic] from gypsum-containing slurries containing stucco, pregelatinised starch, a naphthalenesulfonate dispersant, and sodium trimetaphosphate.”
It then discusses preferred quantities for these additives, and other ingredients that may be used in the slurry including: binders, paper fibre, glass fibre and accelerators. It also notes that a soap foam is added to the slurry to introduce air voids and reduce the density of the core in the final gypsum containing product.
Paragraph [0013] explains why bonding layers are provided to composite gypsum boards. It states:
“Since greater than half of the composite gypsum boards by volume may consist of air voids due to foam, the foam can interfere with the bond between the foamed low density set gypsum core and the paper cover sheets. This is addressed by providing a non-foamed (or reduced-foamed) bonding high density layer on the gypsum core-contacting surfaces of both the top cover sheet and the bottom cover sheet prior to applying the cover sheets to the core.”
In other words, bonding layers are provided on both sides of the core to improve bonding of the cover sheets to the core, which may otherwise be difficult because the core is foamed. This paragraph also explains how composite boards are made, wherein sequentially:
· high density slurry is applied to a first cover sheet to provide a first bonding layer;
· foamed slurry is applied to the first bonding layer to form a formed core;
· the second bonding layer, having previously been applied to the second cover sheet, is applied to the foamed core; and
· the composite product is allowed to set and dry.
Paragraph [0014] states:
“Soap foam is required to introduce and to control the air (bubble) void sizes and distribution in the foamed set gypsum core, and to control the density of the foamed set gypsum core… Although preferably no soap will be used in the non-foamed bonding high density layers, if soap is used in reduced-foamed bonding high density layers, the amount will be about 5% by weight or less of the amount of soap used to make the foamed low density set gypsum core.”
This passage also presumes that the composite gypsum boards have a foamed set gypsum core, as well as bonding layers.
Paragraph [0015] notes that 10-16 wt % of the slurry forming the final board will be high density bonding layer slurry. Preferably 6-9 wt % of the board slurry will form the top bonding layer, while 4-7 wt % will form the bottom bonding layer. In other words this passage discloses that 10-16% of the slurry will form bonding layers, of which 6-9% will form the top bonding layer and 4-7% will form the bottom bonding layer. This disclosure therefore presumes that the final board will have two bonding layers. The dry density of the bonding layer can be about 45-70 pcf and the thickness of the bonding layers will range from about 2-7 mils. Paragraphs [0016]-[0018] discuss useful cover sheets and note they may be made of paper, although other materials such as fibrous glass mats may be used.
Paragraphs [0019]-[0028] detail the use of: naphthelenesulfonate; trimetaphosphate salt; stucco; and starch. Notably, while use of naphthelenesulfonate and trimetaphosphate salt are respectively described as “preferred”[62] and “optional”[63], the use of starch is described as follows:
“[s]tarches, including pregelatinised starch in particular, must be used in gypsum-containing slurries prepared in accordance with the present invention.”
In this context I find “must” a strong word to select.
[62] Ibid, [0019].
[63] Ibid, [0023].
The specification provides examples beginning at paragraph [0034]. In the examples gypsum slurry formulations comprising pregelatinised starch, naphthelenesulfonate dispersant, and trimetaphosphate are used to produce boards which are then compared against boards made using prior art compositions. Boards made using inventive slurry composition are found to provide reduced weight with adequate or increased strength properties. It is worth noting that Examples 1-6 relate to boards not comprising high density bonding layers and that only Examples 7 and 8 are described as relating to composite gypsum boards. In Examples 7 and 8 the composite gypsum boards are made according to the following process:
“Dry powder pregelatinised corn starch was used to prepare the slurry. Heavy Manila paper (60 lb/MSF, calliper 0.018 in.) was used as the top (face) cover sheet, to which was applied 6-8% by weight of the non-foamed high density gypsum slurry having a wet density of 80 pcf, across the entire surface of the paper. After application of the main foamed slurry, the bottom (back) cover sheet was applied, (News-Line paper -42 lb/MSF, caliper 0.0125 in.) which included on its gypsum core-facing surface 4-6% by weight of the non-foamed high density gypsum slurry having a wet density of 80-85 pcf, across the entire surface of the paper.”[64]
While the examples should be properly taken to exemplify the invention and not to necessarily impose limitations on its scope, they are nevertheless consistent with disclosure of a composite board comprising top and bottom bonding layers and cover sheets, and a foamed core made from a foamed gypsum slurry containing stucco and pregelatinised starch.
[64] Ibid, [0057].
It is important to recognise that the consistory statements form part of the disclosure and must not be discounted. Paragraph [0008e] suggests that the second bonding layer is a preferable feature of the invention. Similarly paragraph [0008j] suggests that it is preferable to form the set gypsum core with foam and starch. While the consistory statements may in isolation widen the scope of the term “composite gypsum board”, the body of the specification in an overall sense consistently relates to, presumes, and discloses improvements in a composite gypsum board according to its traditionally understood meaning. Accordingly the specification teaches that bonding layers are provided to improve adhesion of the two cover sheets to the core, which would otherwise adhere insufficiently because the core is foamed.[65] There is no disclosed or apparent use for the bonding layers outside this context. To the extent it may be relevant, I further note that specification does not disclose even an intermediate dry gypsum board comprising only a core and a single bonding layer. Rather, in the disclosed method of production a wet product comprising a foamed core, two bonding layers and two cover sheets is set and dried.[66]
[65] Ibid, [0006], [0013].
[66] Ibid, [0013], [0057].
The body of the specification does not truly contemplate, or otherwise make a real and reasonably clear disclosure of, a composite board without a foamed low density set gypsum core; top and bottom non-foamed (or reduced-foamed) high density bonding layers; and top and bottom cover sheets. To the extent claims 1-21 define a board not limited to these features, they define matter that is not fairly based.
The invention is broadly taught to improve composite gypsum boards by reducing weight and providing thinner bonding layers while retaining strength properties. The specification clearly teaches that in order to achieve this result one must:
· provide both bonding layers with a thickness of about 2 mils to less than 7 mils; and
· use a gypsum slurry comprising stucco and pregelatinised starch.
To the extent claims 1-21 claim a board not limited to these features, they are not fairly based.
USG’s submissions
USG submit that the claims need not take all of what is disclosed in the specification, and there may be fair basis notwithstanding that there is other material disclosed therein. I agree with this general statement. The claims need not, for example, include use of naphthalenesulfonate dispersant in the slurry, which is an optional, preferred feature of the matter disclosed.[67]
[67] Ibid, [0010], [0019], [0021], [0022].
In relation to the features I identify above, USG submits that the claims are not inconsistent with what is disclosed, as the claims leave open the possibility of including these features and do not exclude them. I do not consider USG’s submission to follow the legal principles I identify above. It is inconsistent to define as optional what is disclosed to be necessary. In doing so one claims matter that “travels beyond” [68] what is in substance disclosed.
[68] Lockwood v Doric [2004] HCA 58, [57]; 217 CLR 274, quoting Olin Corporation v Super Cartridge Co Pty Ltd [1977] HCA 23, [6]; (1977) 180 CLR 236, 240.
In relation to the foamed core, and use of the stucco and pregelatinised gel, USG additionally submits that these features relate to ingredients used to form a set gypsum core, or to an intermediate step in forming a set gypsum core, while the product claims relate to the final product (i.e. the finished board) itself. USG submit that final product is different from the slurry from which it originates, and that the chemistry of the slurry changes during setting, rehydrating and drying. USG submit it is the final board with the defined core structure that is claimed in the product claims, not the raw materials, slurry, or intermediate and so the use of stucco and pregelatinised gel need not be claimed.
I have determined that the matter disclosed is a composite gypsum board having certain physical properties and being made with a particular gypsum slurry formulation. The specification clearly teaches that the formulation of the slurry affects the properties of the final board and that one must use a particular slurry to provide the finished board.[69] Claims to a product per se may lack fair basis where the matter disclosed is limited to a particular method of providing the product,[70] or to a particular application of the product. [71]
CSR’s submissions
[69] as set out, for example, at paragraphs [0004], [0012], [0026] and the examples.
[70] Olin Corporation v Super Cartridge Co Pty Ltd [1977] HCA 23; (1977) 180 CLR 236.
[71] Atlantis Corporation Pty Ltd v Schindler (1997) 39 IPR 29.
CSR submit that the invention described requires use of 0.5-10.0% pre-gelatinised starch in the slurry. As for example set out at paragraphs [0010] and [0026] of the specification this is not disclosed to be a necessary part of the invention. CSR further submit that the composite gypsum board described is not disclosed to have:
· a density of less than 35 pcf, or a density of between 24 and 35 pcf;
· a dry density differential between the core and the bonding layer of at least 10 pcf;
· a board dry density (pcf) to average core hardness (lb) of less than about 3.2;
· a ratio of nail pull resistance to average core hardness of about 4-8;
· a bonding layer dry density from about 60 to 70 pcf or about 45 to 60 pcf; and
· a dry weight up to about 1400 lb/MSF, a nail pull resistance of 65 lb, an average flexural strength of at least 36 lb in a machine direction and/or 107 lb in a cross machine direction;
These features are described in the consistory clauses and nothing in the remainder of the specification is clearly inconsistent with their inclusion as part of the invention. There is fair basis for a composite gypsum board including these features.
CSR additionally submit that claims 22 and 23 lack fair basis. Claims 22 and 23 relate to a composite gypsum board, and a method of making a composite gypsum board, “substantially as herein described with reference to the examples in the description.” CSR submit that the composite boards disclosed in Examples 7 and 8 do meet the strength requirements set out in the description. This appears to be an argument best related to utility. As a general comment, I would think it a rare situation for an omnibus claim to lack fair basis. CSR have not established that claims 22 and 23 lack fair basis.
Conclusion
Claims 1-21 are not fairly based as they claim matter for which there is no real and reasonably clear disclosure in the body of the specification.
External fair basis
The priority document and specification as originally filed (“the earlier specifications”) are similar to the present specification, with the exception of the claims and the consistory statements. In the earlier specifications the claims and consistory statements uniformly relate to a composite gypsum board having:
· a foamed low density set gypsum core being made from a foamed gypsum slurry containing stucco, and pregelatinised starch;
· top and bottom non-foamed (or reduced-foamed) high density bonding layers; and
· top and cover sheets.[72]
In light of my above findings these specifications, in all parts,[73] really and reasonably clearly disclose a composite gypsum board necessarily having these features. To the extent the the claims define matter not limited to these features they define matter that is not really and reasonably clearly disclosed.
[72] Specification as originally filed, [0007] and claims 1, 17, 27, 38, 52; Priority document, [0008], [0011] and claim 1.
[73] Vehicle Monitoring Systems Pty Ltd v Sarb Management Group Pty Ltd (No 2) [2013] FCA 395, [125], [126].
CSR submits that the earlier specifications disclose that the slurry of the invention requires 0.5-10% pregelatinised slurry. Reviewing the earlier specifications I am satisfied that this range is disclosed in an overall sense as a preferred optional feature. There is a real and reasonably clear disclosure in the earlier specifications of a composite gypsum board not including this feature.[74]
[74] Specification as originally filed, [0010], [0026], claims 1, 17, 27; priority document, [0011], [0027], claim 1
CSR further submit that the earlier specifications do not provide fair basis for a composite gypsum boards having:
· a density of less than about 35 pcf, or a density of between about 24 and 35 pcf;
· a dry density differential between the core and the bonding layer of at least about 10 pcf;
· a ratio of board dry density (pcf) to average core hardness (lb) of less than about 3.2;
· a ratio of nail pull resistance to average core hardness of about 4-8;
· a bonding layer dry density from about 60 to 70 pcf, or about 45 to 60 pcf; and
· a dry weight up to about 1400 lb/MSF, a nail pull resistance of at least 65 lb, an average flexural strength of at least 36 lb in a machine direction and/or 107 lb in a cross machine direction.
Unlike the present specification, there is no explicit disclosure of these features in the consistory statements or claims of the earlier specifications.
A density of less than about 35 pcf, or a density of between about 24 and 35 pcf
CSR submit that there is no disclosure of a composite gypsum board having a density of about 35 pcf or less. CSR notes that claim 1 of the priority document, and claims 1, 17 and 51 of the specification as originally filed, discloses of a composite gypsum board of less than approximately 24 pcf, while claims 36 and 51 of the specification as originally filed discloses a board of 21.6-26.4 pcf. In a general sense however, the earlier specifications disclose a composite gypsum board that is “light weight”.[75] Examples 1-6 of the earlier specifications, while relating to gypsum boards and not to composite gypsum boards comprising bonding layers, give a flavour to what is meant by “light weight”. In Example 5 gypsum boards having a density of 34.94 and 34.63 pcf are described as “light weight”. In Examples 7 and 8 composite gypsum boards having a density of about 25.0 and 25.7 pcf are described as “ultra light weight”. In paragraph [0006] of the priority document,[76] boards having a weight of between 38.4-40.8 pcf are described as “heavy”. The term “light weight”, as used in the earlier specifications in relation to gypsum boards, provides a real and reasonably clear disclosure of a board with a density of below about 35 pcf, and between about 24-35 pcf.
A dry density differential between the core and the bonding layer of at least 10 pcf
[75] Specification as originally filed, [0001], [0007], [0008], claim 27; Priority document, [0002], [0008], [0009].
[76] Specification as originally filed, [0005].
CSR submit that there is no disclosure in the earlier specifications of a dry density differential between the core and the bonding layer of at least 10 pcf. I found above that there is disclosure of a board having a density of below approximately 35 pcf. In the earlier specifications the dry density of the bonding layers is disclosed be between 45-70pcf.[77] Taking the two together I find there to be a real and reasonably clear disclosure of a dry density differential of at least 10 pcf.
A ratio of board dry density (pcf) to average core hardness (lb) of less than about 3.2
[77] Specification as originally filed, [0015]; Priority document, [0016].
CSR submit that there is no disclosure in the earlier specifications of a ratio of board dry density (pcf) to average core hardness (lb) of less than about 3.2. I have found a real and reasonably clear disclosure of a board density of less than about 35 pcf. In the earlier specifications there is also disclosure of an average core hardness of at least about 11 lb.[78] USG submit that dividing 35 by 11 provides a value of about 3.2. However I note that, according to the defined ratio, as the density of a board drops the lower limit of its requisite average core hardness drops correspondingly. The means that a board of 24 pcf need only provide an average core hardness of 7.5 lb. There is no suggestion in the earlier specifications of a relationship between board density and average core hardness such that the average core hardness of lighter boards need not be as strong. Rather, the earlier specifications teach that sufficient core hardness should be maintained even as composite gypsum boards become lighter.[79]
[78] Specification as originally filed, claim 1, [0005], [0006]; Priority document, claim 1, [0006], [0007].
[79] Specification as originally filed, [0005], [0006], [0061], claim 17; Priority document, [0006], [0007], claim 1.
There is no real and reasonably clear disclosure that lower core hardness values may be set off against lower board dry densities. This is in effect what the current feature defines. It is not really and reasonably clearly disclosed.
A ratio of nail pull resistance to average core hardness of about 4-8
USG submit that there is no disclosure in the earlier specifications of a ratio of nail pull resistance to average core hardness of about 4-8. As noted by CSR, claim 1 of the priority document, and claims 1, 17 and 52 of the specification as originally filed, discloses a nail pull resistance of at least about 77 lb and a core hardness of at least about 11 lb. Dividing the two provides a ratio of 7. In examples 7 and 8 composite gypsum boards are produced having a ratio of 7.4 and 6.7 respectively. While this is true, a ratio of 7 could also be provided with:
· a core hardness of about 1 lb, and a nail pull resistance of about 7 lb;
· a core hardness or about 5 lb, and a nail pull resistance of about 35 lb; and
· a core hardness of about 8 lb, and a nail pull resistance of about 56 lb.
Similarly a ratio of 4 could be provided with a core hardness of 11 lb, and a nail pull resistance of 44 lb; while a ratio of 8 could be provided with a core hardness of 10 lb, and a nail pull resistance of 80 lb.
These ratios frankly appear to have little practical meaning. The earlier specifications do not teach or otherwise imply that high nail pull resistance values may set off low core hardness values, or that low values in each may be sufficient provided the ratio of the two is within a certain range. Rather, the earlier specifications more simply teach that composite gypsum boards should have sufficient strength in both.[80]
A bonding layer dry density from about 60 to 70 pcf, or about 45 to 60 pcf
[80] Specification as originally filed, [0005], [0006], [0061], claim 17; Priority document, [0006], [0007], claim 1.
CSR submit that there is no disclosure in the earlier specifications of a bonding layer dry density from about 60 to 70 pcf, or about 45 to 60 pcf. These are merely two subsets of the disclosed range of about 45-70 pcf. [81] There is no suggestion either involves an inventive selection. There is therefore fair basis for the restriction to these subsets.[82]
A dry weight up to about 1400 lb/MSF, a nail pull resistance of at least 65 lb, an average flexural strength of at least 36 lb in a machine direction and/or 107 lb in a cross machine direction.
[81] Priority document, [0016]; Specification as originally filed, [0015].
[82] Cooper's Animal Health v Western Stock Distributors (1987) 11 IPR 20.
CSR submit that there is no disclosure in the earlier specifications of any of:
· a dry weight up to about 1400 lb/MSF (about 33.6 pcf);
· a nail pull resistance of 65 lb; or
· an average flexural strength of at least 36 lb in a machine direction and/or 107 lb in a cross machine direction
USG refers to examples provided in Examples 1-6 wherein:
· boards in Tables 3 and 5 had densities in lb/MSF of: 1451, 1320, 1456, and 1443.
· a board in Table 3 had a nail pull resistance of 65 lb;
· boards in Table 6 had an average flexural strength in a machine direction of 55.6 lb and 60.3 lb, measured against an ASTM standard; and
· boards in Table 6 had an average flexural strength in a cross machine direction of 140.1 lb and 142.3 lb, measured against an ASTM standard of 107 lb.
While I looked to Examples 1-6 to determine what the specification, in an overall sense, meant by “light weight”, I do not consider it appropriate to look to physical properties uncovered in those examples to provide fair basis in relation to a composite gypsum board. The boards in Examples 1-6 are not composite boards and I do not believe their physical properties can be directly attributed to any composite gypsum board.
In relation to disclosure of a dry weight of less than about 1400 lb/MSF, I have found fair basis for a dry weight of less than approximately 35 pcf, and to a dry weight range of between approximately 24-35 pcf. A dry weight of less than 1400 lb/MSF is a subset of that range which is not suggested to involve an inventive selection. It is a mere restriction to a subset of what is taught.[83] I believe it is fairly based.
[83] Ibid.
In relation to a nail pull resistance of at least 65 lb, wherever a required level of nail pull resistance is discussed in the earlier specifications, the requirement discussed is that the board meet, or at least substantially meet, the ASTM standard of 77 lb.[84] There is no real and reasonably clear disclosure that a nail pull resistance of at least 66 lb would be considered acceptable according to the earlier specification. This feature is not really and reasonably clearly disclosed in the earlier specifications.
[84] Specification as originally filed, [0005], claim 1, 17, 52, as a footnote to Tables 3, 5, 6; Priority document, [0006], claim 1, as a footnote to Tables 3, 5, 6.
In relation to flexural strength the earlier specifications note that flexural strength tests were performed on Examples 7B and 7C (the composite gypsum board examples),[85] however the results of that testing are not disclosed. There is no real and reasonably clear disclosure that the composite boards of the invention will have the flexural strength properties defined.
The effect of s 43(3)
[85] The specification as originally filed, [0060]; Priority document [0061].
Sub-section 43(3) states:
“Where a claim defines more than one form of an invention, then, for the purposes of determining the priority date of the claim, it must be treated as if it were a separate claim for each form of the invention that is defined.”
In AstraZeneca AB v Apotex Pty Ltd[87] the applicability of s 43(3) was considered. In that case the Court held that the amended claim in question did not allow for any alternatives or different forms of the invention.[88] I believe the present claims are different. The claims “allow for” a form of composite gypsum board comprising all the features I deem necessary to render it fairly based on the earlier specifications. That the claims allow, for example, for forms having either a second bonding layer or not is clear from the inter-relationship of claims 1 and 7. That the claims allow for forms having a foamed core formed of a slurry comprising stucco and pregelatinised starch is clear from the inter-relationship of claims 1, 12 and 13. While such forms are not explicitly set out as alternatives in individual claims I am satisfied this is what the claims by their terms allow.
Conclusion
[87] [2014] FCAFC 99, [248].
[88] Ibid, [251].
Claims 1-21 define forms of the invention having a deferred priority date of 25 July 2012 and forms retaining their earliest priority dated of 29 September 2006. Omnibus claims 22 and 23 retain their earliest priority date of 29 September 2006.
Sufficiency
As set out in Kimberly-Clark Australia Pty Ltd v Arico Trading International Pty Ltd[89] the test for sufficiency is whether:
“the disclosure enable[s] the addressee of the specification to produce something within each claim without new inventions or additions or prolonged study of matters presenting initial difficulty.”
[89] [2001] HCA 8 at [25]; (2001) 207 CLR 1 at 17 (“Kimberley-Clark”).
CSR made a number of submissions on sufficiency that I will address in turn.
Bonding layer thickness
CSR submits that the application does not teach the skilled addressee how to control the thickness of the bonding layer. CSR refer to Professor Liu’s trial boards that I have noted above, and submit that Professor Liu was unable to provide a bonding layer of the requisite thickness or without a transition layer between the bonding layer and the core. This submission relies on an interpretation of the bonding layer / core interface that I have discussed above and not taken. In view of my construction CSR have not satisfied me that Professor Liu’s trial boards did not comprise bonding layers according to the invention. Just as importantly, Professor Liu mentions that controlling layer thickness in the laboratory is more difficult than in an automated plant.[90] CSR have not established that the PSA could not control bonding thickness as required under plant conditions.
[90] Liu 1, [47], [50]
Bonding layer / core density differential
CSR submits that difficulties in determining the thickness of the bonding layer (i.e. where the bonding layer ends) make it difficult to determine the density of the bonding layer. This submission also relies on a construction of the bonding layer / core interface that I have not taken.
Board density
CSR refer to the examples provided in the specification, specifically example boards 7B and 7C, which have a board density of about 25 pcf. CSR note that these densities are substantially lower than about 35 pcf and submit that the specification does not teach how to achieve a composite board having a dry density of about 35 pcf. The claims relate to a board having a density of less than about 35 pcf. A board of about 25 pcf falls within the scope of the claims, which is all that is required under Kimberley-Clark.[91] As an aside, CSR have not satisfied me that the PSA, having been taught how to make a lighter board, could not uninventively provide a denser board as desired.
[91] [2001] HCA 8, [25]; (2001) 207 CLR 1, 17.
Strength characteristics
CSR submit that the composite boards produced in examples 7 and 8 are not disclosed as meeting various strength requirements of the claims. The board of example 7C is disclosed as having a nail pull resistance of 83.1 lb and a core hardness of 10.9 lb. CSR contend that 10.9 does not constitute “at least about 11” however I would say that it is sufficiently close to 11, and that the board of example 7C is disclosed to possess the claimed strength properties. CSR alternatively submit that the board of example 7C was made using wet pre-gelatinised starch, and that the specification therefore teaches this feature to be essential. As CSR acknowledge this is matter for fair basis or utility and not sufficiency. I have already determined that use of pre-gelatinised starch, though not necessarily wet pregelatinised starch is a necessary part of the matter disclosed in the body of the specification.
Whether the examples are disclosed as meeting the various strength requirements or not, the relevant question is whether the specification as a whole provides sufficient information for the PSA, armed with the CGK, to uninventively produce something within each claim. This brings me again to Professor Liu’s trial boards.
Strength results for Professor Liu’s trial boards are tabled in his first declaration.[92] According to these results he appears to have provided the requisite strength and density properties. Even were he to not I note that, in an effort to prove that boards of invention could be made without using a metaphosphate salt, he did not include one in his slurry formulation.[93] It is plausible that Professor Liu, or the PSA, could have made stronger boards using metaphosphate salts as taught in the specification.
[92] Liu 1, [38].
[93] Ibid, [19], [29], [40].
Composite gypsum board without cover sheet(s)
CSR submit there is no teaching on how to prepare a composite gypsum board without the use of cover sheets. A composite a gypsum board with cover sheets falls within the scope of the claims and therefore an enabling disclosure of such a board is sufficient under Kimberley-Clark.[94]
[94] [2001] HCA 8, [25]; (2001) 207 CLR 1, 17.
Summary of sufficiency
CSR have not established that the specification lacks sufficiency in respect of any claim.
Utility
All within the scope of the claim must be useful if the claim is not to fail for inutility. A claim is bad if it covers means that will not produce the desired result even if a skilful person would know which means to avoid.[95] However, claims should be construed in a common sense way to avoid embodiments understood by the person skilled in the art to be totally impractical and contrived.[96]
[95] Norton and Gregory Limited v Jacobs (1937) 54 RPC 271, 276; Welch Perrin & Co Pty Limited v Worrel [1961] HCA 91; (1961) 106 CLR 588, 601; Martin Engineering Co v Trison Holdings Pty Ltd (1989) 14 IPR 330, 337.
[96] Austal Ships Pty Ltd v Stena Rederi Aktiebolag [2005] FCA 805, [240].
CSR submit that a number of promises are made on a fair reading of the specification, such as that:
“trimetaphosphate salt to hitherto unknown levels in the presence of a specific dispersant makes it possible to achieve proper slurry flowability with unexpectedly reduced amounts of water, even in the presence of high starch levels.”[97]
[97] Present specification, [0004].
In this example the promise is made in respect of trimetaphosphate. What does the specification promise of the invention? Reviewing the specification I consider these statements relevant:
· “This invention pertains to unique light weight composite gypsum boards having high strength.”[98]
· “Conventional gypsum wallboards have adequate strength for working, and meet standard test requirements such as nail pull (77 lb) and core hardness (11 lb). However, conventional wallboards are heavy, typically weighing up to 1600-1700 lb/MSF. If a way could be found to produce a high strength gypsum wallboard in which board weight (and density) is significantly reduced, without adversely affecting nail pull and hardness characteristics, this would represent a useful contribution to the art.”[99]
· “If a way could be found to make a low density set gypsum board using thinner, lighter bonding layers, without sacrificing core hardness or other important board properties, this would represent a useful contribution to the art.”[100]
· It has now unexpectedly been found that the preparation of a foamed low density set gypsum core using thinner, lighter top and bottom non-foamed (or reduced foamed) bonding high density layers to attain good bonding of a heavy top (face) cover sheet and a bottom (back) cover sheet, can provide a composite gypsum board having nail pull resistance, core hardness, and board strength.[101]
· “As illustrated in Table 8, the Example 7C. composite board exceeds the ASTM standard for nail pull resistance, and essentially meets the core hardness standard (see Table 6). This demonstrates that the use of strong, heavy face paper and regular back paper, both adhered to a low density core using a non-foamed high density bonding layer, can provide a board having light weight, and increased strength.”[102]
[98] Ibid, [0001].
[99] Ibid, [0005].
[100] Ibid, [0006].
[101] Ibid, [0009].
[102] Ibid, [0061].
In view of the above disclosures I find that the promise made of the invention is to provide a composite gypsum board that is light weight while providing sufficient strength. Specific strength characteristics identified relate to average core hardness and nail pull resistance. This construction is consistent with Mr Ball’s statement:
“The Patent Application AU 2007-302768 describes a composite gypsum wallboard of low density: about 35 pcf or less (560 kg/m3). Despite this low density the product meets ASTM C473 on the key strengths of (i) Core Hardness, (ii) Nail Pull, and (iii) Flexural Strength.”[103]
[103] Ball 1, [9]
Professor Liu, in his first declaration states:
“Bob Bruce also states at paragraph 6 that the claims define just a single distinguishing feature, a dry density of 35 pcf or less. I disagree. The patent application describes how to make a low density, very lightweight gypsum board with a bonding layer that can meet or exceed industry standards, and can be as strong as much heavier gypsum boards.”[104]
[104] Liu 1, [11].
Mr White also states:
“In my view, the invention set forth in the present claims represents a remarkable accomplishment since industry experts thought producing a composite gypsum wallboard with such a combination of bonding layer, ultra light weight, and high strength could not be realized on a practical basis as set out in the present application.”[105]
and:
“The strength properties of the wallboard must be maintained to meet industry standards such as the “ASTM C473 standard.” In numerous markets, the ASTM C473 tests establish the industry standards and customer expectations for strength performance criteria, including core hardness and nail pull resistance. If a particular test within ASTM C473 is not met, the customers will consider the product a failure for that tested property.”[106]
[105] While 1, [11].
[106] Ibid, [7].
In other words, according to Mr White’s declaration, the invention claimed relates to a high strength composite gypsum board, however if a composite gypsum board does not meet the ASTM C473 standards for average core hardness and nail pull resistance, it will not meet customer expectations for strength.
While USG agree that the promise of the invention relates to a lightweight composite gypsum board having high strength, its submits that the boards claimed are limited to a high strength board. My issue with this submission was best described by Professor Liu:
“the claims only require that the ASTM test procedures be used to determine the value being studied. In other words, as long as the value as recited in a given claim is met when tested according to the ASTM procedures, it does not matter that the value is below the minimum values stated in the ASTM standards. The claimed invention, again, does not have to be commercial board.”[107]
[107] Liu 2, [19].
A composite gypsum board produced and falling within the scope of independent claims 1 and 15 will not necessarily provide high or sufficient nail pull resistance according to objective industry standards. A composite gypsum board produced and falling within the scope of independent claims 2, 3, 16 and 17 will not necessarily provide high or sufficient average core hardness or nail pull resistance according to objective industry standards. Claims 3 and 17 in particular may allow for very low results in both while still falling within the scope of the claims. To that extent, I find that claims 1-21 includes matter that will not necessarily provide a high strength board to any objective standard as promised.
USG submit that meeting the relevant standards imports to the promise that the boards are commercially viable. USG refers to several authorities noting that commercial viability is not an appropriate consideration in determining utility.[108] To be clear, this is not a matter of whether those in the industry would see the boards as useful in the sense that they may wish to buy them. It is instead a matter of whether what is claimed allows for composite gypsum boards that would be objectively seen as not meeting the promise of high or sufficient strength.
[108] Décor Corporation Pty Ltd & Anor v Dart Industries Inc (1988) 13 IPR 285, 394; SNF (Australia) Pty Ltd v CIBA Speciality Chemicals Water Treatments Ltd & Ors (2011) 92 IPR 46, [288]; Advanced Building Systems Pty Ltd & Anor v Ramset Fasteners (Aust) Pty Ltd (1988) 194 CLR 171, [24].
I note that the ASTM C473 standard is a standard of the United States of America. The Australian standard is AU 2588.[109] Where standards relating to strength differ between countries I accept that the PSA’s identification of what constitutes high or sufficient strength may also vary. Nevertheless, to the extent claims 1-21 cover composite gypsum boards not meeting relevant strength minimum standards, they cover boards that do not achieve the promise of the invention.
[109] GJN-4.
Omnibus claims 22 and 23 refer to the examples, and that it appears Examples 7 and 8 do not provide a composite board meeting all the relevant strength standards. In particular, I am not sure “essentially”[110] meeting the core hardness standard is sufficient for an industry minimum standard. However I am not practically certain the boards would not meet the relevant Australian standards and so CSR have not discharged its onus in relation to these claims.
[110] Present specification, [0061].
CSR further submit that additives such as wet pregelatinised starch must be used to achieve high strength. CSR have not provided evidence clearly establishing this as fact.
CSR have established that claims 1-21 lack utility.
Novelty
The general test for lack of novelty is the reverse infringement test. The classic formulation of this test was given by Aickin J in Meyers Taylor Pty Ltd v Vicarr Industries Ltd:[111]
"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".
This test is satisfied if the alleged anticipation discloses all the essential features of the invention as claimed.[112] Australian courts have often cited, with approval, the words of the UK Court of Appeal in The General Tire & Rubber Company v The Firestone Tyre and Rubber Company Limited:[113]
“If the prior inventor's publication contains a clear description of, or clear instructions to do or make, something that would infringe the patentee’s claim if carried out after the grant of the patentee's patent, the patentee's claim will have been shown to lack the necessary novelty, that is to say, it will have been anticipated. The prior inventor, however, and the patentee may have approached the same device from different starting points and may for this reason, or it may be for other reasons, have so described their devices that it cannot be immediately discerned from a reading of the language which they have respectively used that they have discovered in truth the same device; but if carrying out the directions contained in the prior inventor's publication will inevitably result in something being made or done which, if the patentee's patent were valid, would constitute an infringement of the patentee's claim, this circumstance demonstrates that the patentee's claim has in fact been anticipated.”
[111] [1977] HCA 19 at [20], 137 CLR 228 at 235.
[112] Nicaro Holdings Pty Ltd v Martin Engineering Co (1990) 91 ALR 513, 517.
[113] [1972] RPC 457, 485-486 (“General Tire”).
I have already determined that claims 1-21 claim matter having a deferred priority date of 25 July 2012. As a result CSR are able to rely on each of the following as relevant prior art.
D6 Kurt Peterson, “Engineered Gypsum Panels, the Development and Application of Densified Zones at the Paper/Core Interface of Gypsum Panels” – 6th International Conference of Natural and Synthetic Gypsum, May 2000;
D16Images of Gypsum board manufactured by Canadian Gypsum Company (CGC) and marketed as “Sheetrock”; manufactured in Montreal in late September 1999; commercially available in at least October 1999;
D18 AU 2001287161 (LAFARGE PLATRES) 14 Feb 2002;
D91 AU 2006258027 (UNITED STATES GYPSUM COMPANY) 21 December 2006;
D92 AU 2006258110 (UNITED STATES GYPSUM COMPANY) 21 December 2006;
D93 AU 2007322350 (UNITED STATES GYPSUM COMPANY) 29 May 2008; and
USG’s commercial use of a product embodying the invention from May 2008.D6
D6 is a conference paper summarising efforts to reduce gypsum board weight[114] and optimise its strength-to-weight ratio.[115] It describes:
· use of densified zones at the paper core interface and different methods of providing densified zones;[116]
· improving core structure by providing a preferred core void distribution;[117] and
· using pre-gelatinised starch to fortify the crystal matrix and to preserve the paper-to-core bond.[118]
[114] D6, page 9-1.
[115] Ibid, 9-2.
[116] Ibid, 9-2 and 9-3.
[117] Ibid, at 9-7, 9-8.
[118] Ibid, 9-8, 9-9.
During its discussion of preferred core void distributions[119] D6 refers to US 5643510 (“the Dial-a-Bubble patent”), which CSR notes describes a gypsum board having a board density of approximately 36 pcf. Dr Bruce summarises the disclosure of D6 as follows:
“The conclusion of D6 expressly describes the combination of densified zones at the paper core interface (i.e. bonding layers) and does so in the context of lightweight board, including board such as that described in Dial-a-Bubble that has a board density of 36 pcf. Within the manufacturing tolerances of the gypsum board industry, I consider that 36 pcf could be considered to be ‘about 35 pcf’. D6 also discloses, at page 9-2, examples of bonding layers including a bonding layer with a thickness of less than 0.005 mils (0.127 mm). In my opinion therefore, D6 discloses all of the features that are disclosed in the Application.”[120]
[119] Ibid, 9-7.
[120] Bruce 2, [86].
While D6 refers to features of the claimed invention individually (whether “36 pcf” constitutes about “35 pcf” remaining a matter for debate), it clearly does so while describing separate developments in the art. It does not provide clear instructions to make any single composite gypsum board according to the claimed invention. CSR have not established that any claim lacks novelty in view of D6.
D16
As a matter of initial formality, the Statement of Grounds and Particulars relates D16 to images of gypsum board manufactured by Canadian Gypsum Company (CGC) and made commercially available in 1999. It is not clear when these images were taken or when they became publicly available. It is therefore not clear to me that these images of themselves constitute relevant prior art. However CSR’s evidence and submissions actually relate to the commercial availability and sale of the relevant gypsum board product (“the product”) as an act making prior art information publicly available. CSR allege that claims 1-14 lack novelty in view of the product’s public availability and sale.
The product was obtained and tested by Dr Bruce in September 2009.[121] According to Dr Bruce’s test results the board had a density of 35.3 pcf; a nail pull resistance of 77 lbs; and an average core hardness of 19.[122] Dr Bruce noted in 1999 that the board appeared to include “hard facing” (i.e. bonding layers) though he did not test the bonding layer thickness at the time.[123] He did however retain a sample of the board, with which he later conducted optical microscope imaging to determine bonding layer thickness.[124] The results demonstrated a first bonding layer thickness of 0.40-0.041mm (about 16 mils); and a second bonding layer thickness of 0.67-0.97mm (26-38 mils).[125] Dr Bruce does not mention if he tested the density of the bonding layers.
[121] Bruce 2, [74].
[122] Ibid, [75], [76].
[123] Ibid, [77].
[124] Ibid, [78].
[125] Ibid, [79].
CSR acknowledge that the gypsum board tested has a bonding layer thickness greater than 7 mils. CSR submit that the specification itself does not describe bonding layers of less than 7 mils thick; however I consider this irrelevant for novelty. In terms of novelty (and inventive step), there is no evidence suggesting that the thickness of the bonding layer would not materially affect the way a composite gypsum board would work. A first bonding layer thickness of between 2 to 7 mils is an essential feature of the invention defined in claims 1-14.
As CSR’s submissions relate to disclosure of information through an act it is also appropriate to consider the level of disclosure required. In Jupiters Ltd v Neurizon Pty Ltd[126] Hill, Finn and Gyles JJ noted that the disclosure must be enabling. In Damorgold Pty Ltd v JAI Products Pty Ltd[127] Bennett J noted that the disclosure must disclose the essential integers of a claim in such a manner that the PSA:
“would at once perceive, understand and be able practically to apply the invention without making further experiments or gaining further information before the invention can be made useful.”[128]
[126] [2005] FCAFC 90, [138], [147].
[127] [2015] FCAFC 31, [12].
[128] Damorgold Pty Ltd v JAI Products Pty Ltd [2015] FCAFC 31, [12].
116. I consider Dr Bruce’s evidence relevant to what information the PSA would glean from analysis of a composite gypsum board. Dr Bruce identified the density of the board,[129] and whether the board met particular strength requirements.[130] He also “suspected” that the board was made using “dial-a-bubble” technology.[131] Professor Liu additionally demonstrated that the PSA could determine a density profile for a gypsum board product.[132] What is not clearly established in the evidence, however, is that the PSA would be able to reproduce a board having the same properties from by analysing it. At a guess I expect analysis techniques may be required to determine the conditions or techniques through which the board was made, and/or the ingredients or additives forming the board. Without this kind of evidence I am not satisfied sale of a composite gypsum constitutes an enabling disclosure of how to produce it. CSR have not established that any claim lacks novelty in view of D16.
[129] Bruce 2, [74].
[130] Ibid, [76].
[131] Ibid, [77].
[132] Liu 2, [38].
D18
D18 is a patent document directed to lightweight gypsum board products.[133] The lightweight gypsum board can have a density of between 32-35 pcf.[134] In terms of bonding layers, CSR directed me to a passage at page 3 lines 15-18:
“US Patent No. 5,714,032, issued to Ainsley et al., discloses a two stage mixer. Foam is added to a gypsum slurry in a second mixer and the foamed gypsum is discharged and, with unfoamed gypsum slurry diverted from the first mixer, forms a gypsum board product.”
[133] D18, page 1, lines 5-10.
[134] Ibid, page 18, lines 26 and 27.
CSR submits that when these slurries are applied to paper coversheets, bonding layers are formed between the core and the paper coversheets. This passage forms part of the background information provided in D18. It is a background description of what others have done and does not represent a clear instruction in relation to the board taught in D18. CSR have not established that any claim lacks novelty in view of D18.
D91-D93
D91-93 provide largely equivalent disclosures and have been considered together by both parties. D91-D93 are patent applications applied for by USG. They each relate to a lightweight gypsum board product retaining sufficient strength properties. They also reproduce large amounts of information disclosed in the present application. They do not however disclose a composite gypsum board comprising a dense bonding layer. CSR have not established that any claim lacks novelty in view of D91-D93.
Commercial use
CSR made a submission based on an admission made in evidence by Mr White:
“[c]ommercial products utilizing the combination of claimed features have been sold by USG since May 2008 from USG’s East Chicago plant on a developmental basis in the United States, and were officially launched in North America in July 2010.”
Whether the sale occurred is be a matter of “primary” facts, analogous to whether a document has been published, which may be established on the balance of probabilities.[136] There is no evidence contradicting Mr White’s admission and I consider it more likely than not that the boards were sold as he declares. However, two further matters are relevant:
· CSR have not established that the boards sold did not fall within the scope of matter fairly based on the earlier specifications and as such related to forms of the invention I have assigned an earlier priority date, and
· CSR have not established that sale of a gypsum board would provide an enabling disclosure to the PSA of how to reproduce it.
CRS have not established that any claim lacks novelty in view of Mr White’s comments.
[136] Aspirating IP Limited v Vision Systems Limited [2010] FCA 1061, [35].
Summary of novelty
CSR have not established that any claim lacks novelty.
Inventive step
Subsection 7(2) of the Act[137] states that an invention is taken to involve an inventive step unless it would have been obvious to a person skilled in the art in the light of the common general knowledge, considered alone or together with the prior art. A document is prior art for this purpose if “a skilled person mentioned in subsection (2) could, before the priority date of the relevant claim, be reasonably expected to have ascertained, understood, regarded [the document] as relevant.”[138]
[137] 1990 (Cth).
[138] Ibid, s 7(3).
The test for whether an invention is obvious is to ask whether it would have been a matter of routine to proceed to the claimed invention. In Wellcome Foundation Ltd v V.R. Laboratories (Aust.) Pty Ltd [1981] HCA 12 at [45], 148 CLR 262 at 286 Aickin J stated:
"The test is whether the hypothetical addressee faced with the same problem would have taken as a matter of routine whatever steps might have led from the prior art to the invention, whether they be the steps of the inventor or not."
The problem to be solved
In AstraZeneca AB v Apotex Pty Ltd[139] the Court noted:
“If the problem addressed by a patent specification is itself common general knowledge, or if knowledge of the problem is s 7(3) information, then such knowledge or information will be attributed to the hypothetical person skilled in the art for the purpose of assessing obviousness. But if the problem cannot be attributed to the hypothetical person skilled in the art in either of these ways then it is not permissible to attribute a knowledge of the problem on the basis of the inventor’s “starting point” such as might be gleaned from a reading of the complete specification as a whole.”
[139] [2014] FCAFC 99, [203].
Each party identified the problem as: existing composite boards, while having sufficient strength properties, are heavy. Mr White, in particular, notes:
“removing weight from gypsum wallboard while maintaining strength performance is a very difficult task. The gypsum panel envelope formed between the two sheets of paper must have its volume filled. When gypsum is removed from the board and replaced with air or other expensive lightweight filler to complete the envelope’s volume, it results in a significant loss of strength.”[140]
I have noted above that the claims are not actually limited to a board having what would be objectively viewed as “sufficient strength properties”. Claims 3 and 17 for example would allow a board having a core hardness of about 5 lb, and a nail pull resistance of about 35 lb, to fall within the scope of the claims. These two values would fall well below relevant industry standards and expectations. Nevertheless I agree that the identified problem is relevant to the present invention.
[140] White 1, [8].
In view of the common general knowledge alone
I am satisfied that a number of matters form part of the common general knowledge. These include:
· composite gypsum boards comprising a bonding layer;[141]
· techniques for depositing bonding layers on the face and back cover paper of a gypsum board;[142]
· the requirements under ASTM C473 including nail pull resistance, core hardness and flexural strength and the need to comply with this standard;[143]
· use of strength additives to improve the strength of gypsum boards;[144]
· a historical trend in the industry toward reduced board weight.[145]
[141] Neil 2, [8].
[142] Ibid, [10].
[143] Ibid, [17].
[144] Ibid, [14], [16].
[145] Neil 2, [16]; Bruce 2, [42].
CSR submit that, in light of identified knowledge such as that above, a lighter composite gypsum board having requisite strength was obvious. CSR essentially submit that, because people in the art were seeking to provide a lighter composite gypsum board with strength properties, it would be obvious to provide one. However, this submission ignores evidence acknowledging that such a result, while being clearly desirable, was actually difficult to achieve.[146]
[146] Bruce 1, [6], [7], [13]; Neil 1, [9]; Liu 1, [12]; White 1, [8].
CSR have provided evidence establishing a general trend toward providing lower density gypsum boards as technology has advanced.[147] However it has not established that the PSA had, at the priority date, arrived at a point where he or she would as matter of routine have provided a gypsum board comprising the density, strength properties, and bonding layer claimed. In J. Lucas (Batteries) Ltd. and Another v Gaedor Ltd. and Others[148] Whitford J stated:
“If an invention has resulted in the solution of a problem which has been troubling industry for years and achieves immediate success upon its introduction, then the suggestion after the event that the step was obvious inevitably rings a little hollow.”
[147] Neil 2, [16]; Bruce 2, [42].
[148] (1978) RPC 297, 358.
The evidence establishes that it was difficult to provide a lighter board while maintaining requisite strength properties.[149] As I have noted above, the claims include within their scope composite gypsum boards that would not be objectively seen to have requisite strength properties. That being so, CSR have not led evidence establishing that the PSA would as a matter of routine have provided a lighter composite gypsum board as claimed having:
· an average core hardness of at least about 11 pounds (about 5 kg);
· the board has a ratio of dry density (pcf) to average core hardness (lb) of less than about 3.2; or
· the board, when at a thickness of about ½ inch (about 1.3 cm), has a nail pull resistance to average core hardness ratio from about 4 to about 8.
[149] Bruce 1, [6], [7], [13]; Neil 1, [9]; Liu 1, [12]; White 1, [8].
CSR have not established that any claim lacks an inventive step in view of the common general knowledge.
In view of the prior art
In view of the deferred priority date CSR relied on the following as relevant prior art:
D1 AU 638696 B1 (DOMTAR INC.) 08 July 1993;
D2 US 5085929 A (BRUCE et al.) 4 February 1992;
D3 US 5116671 A (BRUCE et al.) 26 May 1992;D5Brian Burrows “A Decade’s Experience if Gypsum Board Weight Reduction in the US” – Presented at the 14th International Building Conference 20 to 23 September 2000;
D6 Kurt Peterson; “Engineered Gypsum Panels, the Development and Application of Densified Zones at the Paper/Core Interface of Gypsum Panels” – Present at the 6th International Conference of Natural and Synthetic Gypsum, May 2000;
D12 US 2004/0134585 A1 (CALLAIS et al.) 15 Jul 2004;
D16Images of Gypsum board manufactured by Canadian Gypsum Company (CGC) and marketed as “Sheetrock”; manufactured in Montreal in late September 1999; commercially available in at least October 1999;
D18AU 2001287161 A1 (LAFARGE NORTH AMERICA INC.) 14 February 2002
USG’s commercial use of a product embodying the invention since May 2008; and
The priority documentD1-D3
Each of D1-D3 are treated by the parties as providing a similar disclosure. CSR submit that D1-D3 disclose all the features of the independent claims of the patent, with the exception of the claimed density. CSR submit that it would have been obvious to lower the density by, for example, using different foaming agents.[150]
[150] Bruce 2, [100]; Neil 1, [46]
Even were I to accept that the PSA would as a matter of routine have tried using different foaming agents to lower the board density, CSR have led no evidence establishing that trying different known foaming agents would lead to a product falling within the scope of the claims. As noted by Dr Bruce:
My own invention, as described in AU638696, US 5,085,929 and US 5,116,671 would describe a core structure that matched that of the subject invention, but probably would not allow the strength to be achieved at the same core density. The use of the unique combination of additives [as disclosed in the specification]… would be necessary to achieve the strength parameters.[151]
Dr Bruce appears to opine that it would require the specific strengthening additives of the invention, and not merely any known strengthening additives, to achieve the result desired.
[151] Bruce 1, [10].
I am not satisfied that any claim lacks an inventive step in view of D1-D3.
D5 and D6
D5 is a conference article noting the general trend toward lower density gypsum boards and I note it provides a broadly similar disclosure to D6. Similar to D6, while D5 refers to features of the claimed invention individually, it does so in the context of describing separate developments in the art. As I found above in relation to D6, D5 does not provide clear instructions to make any single gypsum board according to the invention.
Dr Bruce and Mr Neil say that D5 discloses a board comprising all features of the invention, with the exception of a density of less than about 35 pcf.[152] They then say it would be obvious to provide a board having a density of less than about 35 pcf.[153] However they do not clearly set out how this could be achieved through any obvious means. Mr Neil notes that strengthening additives are known in the art.[154]
[152] Bruce 2, [90]; Neil 2, [51].
[153] Ibid, [90]; Neil 2, [52], [54].
[154] Neil 2, [54].
Were I to accept that:
· D5 discloses a board comprising all the features of the invention, with the exception of the requisite density; and that
· the PSA would seek to lower the density of boards disclosed in D5 while maintaining strength characteristics using means such as strengthening additives
I would still not be satisfied these efforts would necessarily lead to a board falling within the scope of the claims.
Similar submissions were made in relation to D6 and my conclusions are the same. CSR have not established that any claim lacks an inventive step in view of D5 or D6.
D12
D12 is a patent document setting out a process for making gypsum board. CSR’s submissions are similar to those provided in relation to D1-D3, D5 and D6. CSR submits that D12 discloses all the features of the invention claimed, with the exception of a dry density of 35 pcf of less. CSR submits it would be obvious to modify the disclosed board to be lighter, however it does not establish what steps the PSA would as a matter of routine have taken that would achieve this.
CSR have not established that any claim lacks an inventive step in view of D12.
D16 and USG’s commercial use of a product embodying the invention
I stated above that I am not satisfied sale of a composite gypsum board would constitute an enabling disclosure of how to make it. As I am not satisfied the PSA could reproduce the disclosed composite gypsum boards, I am not satisfied the PSA would be directly led from them to provide a composite gypsum board according to the claims. I also again note that USG’s sale of gypsums boards from May 2008 may have related to forms of the invention fairly based on the earlier specifications and having a priority date of 29 September 2006.
CSR have not established that any claim lacks an inventive step in view of D16 or USG’s commercial use of a product embodying the invention.
D18
As I discussed above D18 discloses a lightweight gypsum board having a density of between 32-35 pcf, however there is no disclosure of such a board comprising a high density bonding layer.
CSR submits that it would be obvious to modify the board disclosed in D18 to provide a bonding layer as claimed. I could potentially accept that, in view of the problem identified and the teaching of D18 toward a lightweight gypsum board having adequate strength properties,[155] the PSA may consider forming a composite gypsum board from the slurry disclosed in D18. However CSR have not established with evidence:
· that the PSA would as a matter of routine have provided a bonding layer of the thickness defined; or
· what would occur if a composite board were made from the slurry of D18. In particular, it is not clear to me what effect this would have on the density or strength of the board, in particular its core hardness and nail pull resistance. I am not practically certain that the invention claimed would be derived from D18.
[155] D18, at for example abstract.
CSR have not established that any claim lacks an inventive step in view of D18.
The priority document
CSR’s submissions mention that the priority document is relied upon as relevant s 7(2) prior art for inventive step. However CSR make no more specific submissions than that and did not refer to the matter at the hearing. The priority document is also not discussed as relevant prior art in evidence. I will comment however that I have found the claims to by their terms allow for different forms wherein certain forms are accorded the earliest priority date of 29 September 2006. The earlier specifications could only become relevant prior art for forms of the invention having a deferred priority date. There is no clear evidence that the PSA would be led from the disclosures of either of the earlier specifications to provide a product falling within forms of the invention having a deferred priority date.
Conclusion
The opposition succeeds on the grounds that claims 1-21 lack fair basis and utility. As these grounds can be overcome by amendment, I will allow the USG an opportunity to amend.
Costs
CSR has been successful in its opposition. Generally costs should follow the event and I see no reason to depart from this approach. I will award costs against USG.
Rhys Munzel
Delegate of the Commissioner of Patents
[86] The Act 1990 (Cth).
[135] White 2, [5].
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