Onesteel Reinforcing Pty Ltd
[2013] APO 42
•19 July 2013
IP AUSTRALIA
AUSTRALIAN PATENT OFFICE
Onesteel Reinforcing Pty Ltd [2013] APO 42
Patent:2007200078
Title:A roof support module
Patentee: Onesteel Reinforcing Pty Ltd
Delegate: P M Spann - Deputy Commissioner of Patents
Decision Date: 19 July 2013
Hearing Date: 25 June 2013
Catchwords: PATENTS – re-examination – revocation – lack of inventive step – invention defined in certain claims found to be obvious in light of admitted common general knowledge – patentee directed to file amendments overcoming the grounds of invalidity.
Representation: Patent applicant: G Munt, Griffith Hack Melbourne
IP AUSTRALIA
AUSTRALIAN PATENT OFFICE
Patent:2007200078
Title:A roof support module
Patentee: Onesteel Reinforcing Pty Ltd
Date of Decision: 19 July 2013
DECISION
The invention defined by claims 3 and 4 and claims 5-8 when dependant on claim 3, as proposed to be amended, is obvious.
Under section 106 I direct the patentee to file amendments overcoming this ground of objection within 60 days of the date of this decision otherwise I will revoke the patent.
REASONS FOR DECISION
Patent application 2007200078 was filed by Onesteel Reinforcing Pty Ltd (Onesteel) on 8 January 2007. It was a divisional application under section 79B from application number 2003248397 which was filed on 25 September 2003 and in turn claimed priority from provisional application 2002951642.
The present application was subject to examination, was accepted, and was granted without opposition on 24 March 2011. On 9 March 2012 Wallington-Dummer filed a request for re-examination followed on 21 March by a revised request citing 3 published patent specifications. The examiner issued a number of re-examination reports which were responded to by the patentee by filing a statement of proposed amendments under s.104 and statements under s.99 disputing the reports.
In considering whether the patent, or claims of the patent, should be revoked under section 101, I have had regard to the re-examination request, the examination reports and the submissions made by the patentee’s attorney under s.99 and at the hearing. I will refer to these where relevant in my reasons below.
The specification
The invention described in the patent relates to mine roof support mesh which is typically bolted to the roof of underground tunnels to stabilise the roof strata. The specification states that:
“Typically, roof support mesh is rectangular and is formed from a first layer of parallel elongate members (generally referred to as ''line wires") and a second layer of parallel elongate members (generally referred to as "cross wires") that are transverse to the line wires and are welded together at the intersections of the wires. Each line wire and cross wire may be a single wire or multiple wires, such as double wires, positioned side by side in contact with each other. Typically, the mesh is 4-5m long and 700-1700mm wide.
In use of the roof support mesh to support a roof strata, such as a roof strata of an underground mine roadway, sheets of mesh are positioned against the roof strata and rock bolts of rock bolt assemblies are positioned to extend through openings in "bolting" sections of the mesh sheets and into holes drilled in the roof strata. Thereafter, tensioning nuts and bearing plates of rock bolt assemblies are positioned on the rock bolts and clamp the mesh sheets to the roof strata.
The standard practice in the Australian mining industry is to bolt a sheet of roof support mesh to a new section of roof strata immediately after the section has been excavated so that there is maximum possible mesh coverage as a roadway is being formed.
Consequently, in the case of excavating a new roadway, the standard practice in the Australian mining industry includes the following sequence of steps repeated
along the length of the roadway:Excavate a section of the roadway, typically l-2m long depending on the roof strata and the width of the roof support mesh being used in that roadway.
Stop excavating when the section has been excavated.
Position a sheet of roof support mesh against the roof, with the line wires transverse to the direction of the roadway, and in overlapping relationship with a previously positioned roof support mesh, drill bolt holes and bolt a required number of bolt assemblies (typically 5) at the overlap regions of the sheets across the width of the roadway.”
The specification goes on to indicate that this procedure results in periodic interruption to the excavation and that the invention is intended to improve the rate of roadway development. This is then said to be achieved by moving the bolting section of the mesh closer to the sheet edge thereby reducing the overlap of adjacent sheets and allowing “a significant increase in maximum bolt spacing for a given mesh size without increasing mesh cost, weight and handling characteristics of the mesh.” The independent claims are in the following terms:
“1. A mine roof support mesh for supporting an area of a roof of a mine, which mesh includes: a first layer of parallel line wires and a second layer of parallel cross wires that are transverse to the line wires and are welded together at the intersections of the wires, the wires being made from steel and having a circular cross-section of at least 4mm in diameter, the line wires including wires that define a bolting section of the mesh, the bolting section being defined by a larger cross-sectional area of wires per unit area of mesh than the remainder of the mesh so as to increase the resistance to shearing the mesh in the bolting section of the mesh, and the centre of the bolting section being less than 125mm from one side of the mesh.
4. A mine roof support mesh for supporting an area of a roof of a mine, which mesh includes: a first layer of parallel line wires and a second layer of parallel cross wires that are transverse to the line wires and are welded together at the intersections of the wires, the wires being made from steel and having a circular-cross section of at least 4mm in diameter, the line wires including wires that define a bolting section of the mesh, the bolting section being defined by a larger cross-sectional area of wires per unit area of mesh than the remainder of the mesh so as to increase the resistance to shearing the mesh in the bolting section of the mesh, and the position of the bolting section being selected so that less than 225mm of the mesh at that side of the mesh is required to overlap a sheet of the mesh with a successive mesh sheet in order to secure the mesh sheets to a roof strata using more rock bolt assemblies passing through the bolting section.”
The difference in the mesh according to the invention compared with the prior art is shown in figure 3 of the specification:
Figure 3a is said illustrate a commercially available mine roof support mesh in accordance with the applicant’s Australian Patents 720908 and 735219. The specification states:
“The most widely used roof support mesh in the Australian mining industry over the last 7 years is a mesh that is described in Australian standard patent application 720908 and Australian petty patent 735219 in the name of the applicant. The roof support mesh is generally rectangular and formed from parallel line wires and parallel cross wires welded together at the intersection of the wires. One side of the mesh is upturned and the other side is down-turned to improve the rigidity of an otherwise flat sheet. The mesh is characterised by a bolting section that is defined by a pair of double line wires adjacent one side of the mesh. The pair of double line wires visually distinguish the bolting section from the other section of the mesh and concentrate reinforcement in the bolting section. Typically, the line wires in the section of the mesh other than the bolting section are spaced apart at 100mm centres and the cross wires in the mesh are spaced apart at 100mm centres and the wire diameters are at least 4mm. The roof support mesh has dominated the Australian market for mesh for underground coal mining since it was introduced into the market 7 years ago”.
Figure 3b reflects the mesh according to the invention with a further modification in figure 3c. Accordingly it can be see that an increase in bolt spacing is achieved by the placement of the bolting section (13) further to the edge of the sheet.
The re-examination
The re-examination request referred to three patent specifications – GB2150950, AU735219, and AU753737 – in asserting lack of novelty and of inventive step. The examiner raised lack of inventive step in the first re-examination report against all 13 claims. The patentee subsequently filed a statement of proposed amendments and submissions. The claims as are proposed to be amended include 9 claims with the independent claims as follows:
1. A mine roof support mesh for supporting an area of a roof of a mine, which mesh includes: a first layer of parallel line wires and a second layer of parallel cross wires that are transverse to the line wires and are welded together at the intersections of the wires, the wires being made from steel and having a circular cross-section of at least 4mm in diameter, the line wires including wires that define a bolting section of the mesh on one side only of the mesh, the bolting section being defined by a larger cross-sectional area of wires per unit area of mesh than the remainder of the mesh so as to increase the resistance to shearing the mesh in the bolting section of the mesh, the bolting section being defined by two groups of line wires, each group defining one side of the bolting section, and each group including two or more line wires that are in contact with each other or are more closely spaced than the other wires in the mesh and thereby visually distinguishing the bolting section from the remainder of the mesh and the centre of the bolting section being 70-120mm from the one side of the mesh.
3. A mine roof support mesh for supporting an area of a roof of a mine, which mesh includes: a first layer of parallel line wires and a second layer of parallel cross wires that are transverse to the line wires and are welded together at the intersections of the wires, the wires being made from steel and having a circular-cross section of at least 4mm in diameter, the line wires including wires that define a bolting section of the mesh on one side only of the mesh, the bolting section being defined by a larger cross-sectional area of wires per unit area of mesh than the remainder of the mesh so as to increase the resistance to shearing the mesh in the bolting section of the mesh, the bolting section being defined by two groups of line wires, each group defining one side of the bolting section, and each group including two or more line wires that are in contact with each other or are more closely spaced than the other wires in the mesh and thereby visually distinguishing the bolting section from the remainder of the mesh and the position of the bolting section being selected so that less than 225mm of the mesh at that side of the mesh is required to overlap a sheet of the mesh with a successive mesh sheet in order to secure the mesh sheets to a roof strata using more rock bolt assemblies passing through the bolting section.”
10. The examiner considered the amendments to be allowable but has maintained that the invention claimed in all the claims is lacking an inventive step in light of AU735219. The examiner in particular has found that the specification for this patent inherently discloses a bolting section being 70-120mm from the side of the mesh and an overlap of less than 225mm because it refers to the minimum spacing between longitudinal wires of conventional mesh as 50mm and a preferred spacing between the longitudinal members forming the bolting section of 40mm. Consequently the examiner concluded that the prior art disclosed the centre of the bolting section being 120mm (50+50+40/2) from the sheet edge. This is illustrated in Figure 4 of AU735219:
Law
11. According to subsections 7(2) and (3) as they were before the commencement of the Intellectual Property Laws Amendment (Raising the Bar) Act 2012, the invention in this case is taken to involve an inventive step, when compared with the prior art base, unless the invention would have been obvious to a person skilled in the art in the light of the common general knowledge in the patent area, either on its own or together with the information specified in subsection (3). This information includes one or a combination of two or more pieces of prior art information being information that the person skilled in the art could be reasonably expected to have ascertained, understood and regarded as relevant. It is well established that the obviousness question can be formulated as follows:
"The test is whether the hypothetical addressee faced with the same problem would have taken as a matter of routine whatever steps might have led from the prior art to the invention, whether they be the steps of the inventor or not." (Wellcome Foundation Ltd v VR Laboratories (Aust) Pty Ltd (1981) 148 CLR 262 at 286)
12. The High Court in Aktiebolaget Hassle v Alpharpharm Pty Ltd (2002) 212 CLR 411 at 433 [53] stated that it is also permissible to use the "Cripps question":
“Would the notional research group at the relevant date, in all the circumstances, which include a knowledge of all the relevant prior art and the facts, directly be led as a matter of course to try the invention as claimed in the expectation that it might well produce a solution to the problem”
13. It is clear that any potential solution to a problem will not be obvious unless it would have been a matter of routine to try that solution, but with the significant caveat that there must be an expectation that the potential solution "might well" solve the problem. It is not necessary that success is guaranteed.
14. As to whether prior art information could be ascertained, understood and regarded as relevant this has been considered by the Full Federal Court in Commissioner of Patents v Emperor Sports Pty Ltd [2006] FCAFC 26; 67 IPR 488 at [29]- [30]) and will generally be a matter of evidence as to what the person skilled in the art would do when faced with the problem at hand (see also Delnorth Pty Ltd v Commissioner of Patents [2013] FCA 165). Evidence for this purpose encompasses conclusions that the Commissioner is entitled to make based on his or her knowledge as an administrative decision maker equipped with technical expertise.
Consideration
15. I accept the patentee’s submission that the problem sought to be addressed by the patent is to increase the rate at which roof support mesh can be installed in underground mine roadways. The common general knowledge in the art is said by its attorney to include a commercial form of the mesh illustrated in figure 3a of the patent “that is in accordance with Australian patents 720908 and 735219”. However it is said that the disclosure of those earlier patents is not common general knowledge. Neither is it conceded that the relevant patent specifications would have been ascertained by a skilled addressee (in my view a mining engineer). While it would seem that the granting of the patents may have been announced in the press including publications that mining engineers may review (eg the Australian Journal of Mining, March/April 2002), I have no particular basis to assume that such an engineer would be prompted to obtain and read the patent in seeking to address the problem. The re-examination requestor also has not provided any evidence that the documents identified in the request would have been ascertained.
16. Accordingly, I do not find that the particular content of the prior art patents is available for the determination of whether what is claimed constitutes an inventive step and consequently I am of the view that the objection taken by the examiner cannot be sustained. Any consideration is therefore limited to whether the invention is obvious in the light of common general knowledge. This, in addition to the matters which the patentee has conceded as indicated above, includes matters of practical knowledge that clearly would be in the mind of an engineer when addressing the problem referred to above. Particularly it would have been known that increasing the rate of roof sheeting could, among other things, be achieved by altering the size and overlap of the sheets. Of course any change would have to take into account other considerations particularly the ability of the mesh to maintain its load bearing capabilities and practicality in the mining environment.
17. I consider that a mining engineer, had they put their mind to it, would have chosen the smallest sheet overlap that was consistent with the load bearing requirements for the roof. In that sense the overlap and placement of the bolting section could be seen as mere design choice as asserted by the requestor. Certainly reducing the overlap does not appear to have required any special accommodation and appears entirely to arise from recognition that reducing the overlap did not significantly reduce load bearing performance.
18. The patentee however asserts that the prior art mesh was well established as the industry standard at the priority date and consequently that a clear motivation to modify the mesh was not apparent. That is, in effect, that persons skilled in the art accepted that the existing mesh already provided an optimum positioning of the bolting section and degree of overlap. Ultimately while the invention on its face appears to be merely an optimisation of an existing product, I cannot in the absence of supporting evidence conclude that the skilled person would have been led as a matter of course to modify the mesh according to the substance of the invention, as opposed to other means by which the problem could be addressed, including means to make installing the existing mesh more efficient. This is more so if according to the obiter in Delnorth and Emperor Sports I am required to be “practically certain” before revoking the patent after re-examination.
19. That said, claim 3 as proposed to be amended is not limited directly by the location of the bolting section in the mesh but on a ‘required’ overlap of less than 225mm. This appears to be based on the bolting arrangement and dimensions shown in figure 3 (an idealised illustration) rather than in practical use. In use the rock bolt will not always be centered in the mesh apertures but its placement will vary according to circumstances and the choice of the operator. In that case it appears that for the known mesh the overlap in normal use will very likely vary between 154mm plus the rock bolt diameter to over 250mm. For a 32 mm rock bolt this would mean a 186mm minimum overlap and for a typical 24mm bolt, 178mm.
20. Consequently I find that the invention defined in claims 3 and also in claim 4 and claims 5-8 when dependant on claim 3 (which add further matters of common general knowledge) is obvious in light of the common general knowledge.
Conclusion
21. The invention defined by claims 3 and 4 and claims 5-8 when dependant on claim 3, as proposed to be amended, is obvious. There is however insufficient evidence to show that the invention claimed in other of the claims is lacking an inventive step.
22. Consequently, as permitted by section 106, I direct the patentee to file amendments overcoming the ground of objection indicated above within 60 days of the date of this decision otherwise I will revoke the patent.
P M Spann
Deputy Commissioner of Patents
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