19 November 2017

Sweet! Patent Office Finds Specification ‘Clear Enough and Complete Enough’ to Support Full Scope of Polypeptide Claims

Completing the puzzleThe Intellectual Property Laws Amendment (Raising the Bar) Act 2012 raised the standard of disclosure in a patent specification, requiring that it be ‘clear enough and complete enough for the invention to be performed by a person skilled in the relevant art’: Patents Act 1990, section 40(2)(a).  This change from the old ‘fair basis’ provision was intended to align Australian patent law with that of the UK and Europe, requiring the disclosure to be commensurate with the scope of the claims, i.e. that the description should be sufficient to enable the skilled person to perform the invention across the full width of the claims.

So far, there has been no judicial consideration of this new enablement requirement, and until recently there was just one Patent Office decision, CSR Building Products Limited v United States Gypsum Company [2015] APO 72, in which the Hearing Officer found that claims directed to light-weight, fire-resistant gypsum panels did not meet the required standard.  In particular, the panels were claimed in terms of their properties – core density, core hardness, Thermal Insulation Index, and fire resistance – however it was found that the specification did not provide a sufficient disclosure of how to achieve those properties, other than by manufacturing and testing samples.  In this particular case, there were a number of process and starting material parameters that could be varied, but no guidance in the specification on how to adjust these parameters to achieve the claimed properties with reasonable certitude.  (For more information on the CSR decision, see Disclosure and Support in Australian Patent Specifications: Raised Bar Trips Applicant in Opposition.)

As of 14 November 2017, however, we now have a second decision from the Patent Office on the ‘clear enough and complete enough’ requirement, this time in favour of the patent applicant: Evolva SA [2017] APO 57.  In this case, the claims relate to ‘methods and materials for enzymatic synthesis of mogroside compounds, and in particular to glycosylating mogrol using Uridine-5’-diphospho dependent glucosyltransferases (UGTs).’  While that might make sense to  biotechnologist, for the rest of us the invention basically covers methods of making compounds similar to those that are naturally-occurring in the fruit of the vine siraitia grosvenorii (luo han guo or monk fruit), which is native to China and Thailand.  The extract of this fruit is 300 times sweeter than sugar, and thus can be used as a low calorie sweetener.

Evolva’s claimed method involves using an enzyme (polypeptide) to catalyse a reaction resulting in the desired mogroside compounds.  Effective polypeptides are defined in the patent specification in terms of five amino acid sequence listings.  However, the claims are not limited to these sequences, but are drafted to encompass polypeptides ‘having at least 90% sequence identity’ to the sequences set out in the listings.  The examiner had objected that the specification did not provide a ‘principle of general application’ which would enable the invention across its full scope, and that the skilled person would therefore need to produce and test every polypeptide having up to a 10% difference from the listed sequences in order to determine which would work, and which would not.  Therefore – the examiner concluded – the claims were not enabled across their full scope, and the ‘clear enough and complete enough’ requirement of section 40(2)(a) was not satisfied.

While this case might seem, at first blush, to be analogous with the CSR decision, the Hearing Officer here reached the opposite conclusion, overruled the examiner’s objections, and directed that the application proceed to acceptance.  The case demonstrates how the question of what constitutes an enabling disclosure is very much specific to the technology at issue, and to the skills and abilities of the person skilled in the art.  It also provides useful further guidance, in the absence of any judicial consideration as yet, on how the Patent Office will approach application of the ‘enablement’ requirement in section 40(2)(a) of the Patents Act 1990.

UK/European Approach to Sufficiency

In view of the fact that the current Australian enablement and sufficiency requirements are intended to align the law with that of Europe and the UK, the Hearing Officer has provided a very useful review of relevant UK authorities, in particular.  As noted at paragraph [23], three main approaches to insufficiency of description have developed in UK case law:
  1. classical insufficiency, where the teaching of the patent does not enable the skilled person to perform the invention without further invention, or where ‘prolonged research, enquiry or experiment’ is required in order to work the invention;
  2. insufficiency by excessive claim breadth, where there may be an enabling disclosure for something falling within the scope of the claim, but not across the full breadth of the claim; and
  3. insufficiency by ambiguity, where the skilled person is unable to determine whether or not they have worked the invention.
The examiner’s objections in Evolva’s case were based essentially on ‘undue burden of experimentation’ and ‘principle of general application’, i.e. insufficiency by excessive claim breadth.  The Hearing Officer identified a number of considerations relevant to these concepts in the UK and European decisions on insufficiency (at [27]-[34]).
  1. The fact that the disclosure need only be enough sets a minimum requirement and it is long-established law that the skilled reader will draw upon their common general knowledge and skills in order to work the invention.
  2. The extent of the disclosure necessary to make the patent sufficient will depend upon the nature of the invention, the scope of the claims and the art in which the invention is made.
  3. The emphasis in relation to undue burden has been on the nature of the work that is required by the skilled person in view of the guidance provided in the specification.
  4. One approach has been to ask whether the skilled person would be required to undertake a ‘research programme’ in order to perform the invention – if so, then the specification is likely insufficient.
  5. Factors that may come into consideration in finding a lack of sufficiency include uncertainty and a lack of predictability, incomplete experimental details, and a lack of guidance in the specification including instructions on how to proceed in case of failure.
The Hearing Office then noted (at [35]) that some of these considerations were reflected in the earlier CSR decision, where various parameters of the fire-resistant panels

… were determined by a number of process and starting material variables, and the specification provided no real guidance on how these could be adjusted to achieve the full combination of properties defined by the claims. The lack of guidance, the uncertainty in the research and the degree of trial and error required led to the determination that there was an undue burden required to perform the invention across the full scope of the claims.

With regard to a ‘principle of general application’, the Hearing Officer drew (at [37]-[39])on decisions of Lord Hoffmann in Biogen Inc v Medeva plc [1996] UKHL 18 and Kirin-Amgen Inc v Hoechst Marion Roussel [2004] UKHL 46, and of Kitchin LJ in Regeneron Pharmaceuticals Inc and Bayer Pharma AG v Genentech Inc [2013] EWCA Civ 93.
  1. A ‘principle of general application’ simply means an element of a claim – no matter how strikingly original, or humble – which is stated in general terms.
  2. Such a claim is sufficiently enabled if one can reasonably expect the invention to work with anything which falls within the general term.
  3. The patentee need not show that the application of a general principle has been proven in every individual instance.
  4. On the other hand, if the claims include a number of discrete methods or products, the patentee must enable the invention to be performed in respect of each of them.
  5. It must be possible to make a reasonable prediction the invention will work with substantially everything falling within the scope of the claim or, put another way, the assertion that the invention will work across the scope of the claim must be plausible or credible.
  6. If it is possible to make such a prediction then it cannot be said the claim is insufficient simply because the patentee has not demonstrated the invention works in every case.
The Hearing Officer also noted (at [40]) the two-step enquiry employed by Arnold J in Eli Lilly and Company v Janssen Alzheimer Immunotherapy [2013] EWHC 1737 (Pat):
  1. first, determine whether the disclosure of the Patent, read in the light of the common general knowledge of the skilled team, makes it plausible that the invention will work across the scope of the claim; and
  2. if the disclosure does make it plausible, secondly consider whether the evidence establishes that in fact the invention cannot be performed across the scope of the claim without undue burden.

Approach to be Followed in the Present Case

Regarding the inquiry to be undertaken in assessing whether Evolva’s specification was sufficient to enable the invention to be performed across the full scope of the claims, the Hearing Officer concluded (at [45]), that:

…regard may be had to the guidance provided in recent UK and EPO decisions on sufficiency, including the consideration of plausibility in relation to claims of excessive breadth. Accordingly, in this case I will follow a process of construing the specification and determining:
    What is the scope of the invention as claimed?
    What does the specification disclose to the skilled person?
    Does the specification provide an enabling disclosure of all the things that fall within the scope of the claims, and in particular:
        (a) Is it plausible that the invention can be worked across the full scope of the claim?
        (b) Can the invention be performed across the full scope of the claim without undue burden?

Application to the Evolva Case

The examiner had considered that the relevant person skilled in the art (PSA) could be a single synthetic chemist, perhaps a PhD candidate.  The Hearing Officer, however, determined (at [54]) that the PSA in this case would be significantly more specialised and highly skilled, namely ‘a team comprising biotechnologists with skills and knowledge of the techniques for the identification and generation of variants (including recombinant techniques), as well as synthetic chemists with a knowledge of the use of enzymes in reactions.’

The first issue in question, in light of the disclosure in the specification, was ‘whether it is plausible that polypeptides which have as low as 90% identity would be capable of catalysing the defined glycosylation reaction’ (at [59]).  The Hearing Officer determined that it was (at [62]):

Given the prior art knowledge of the structure and function of UGTs, I can see no apparent reason why the skilled person would not consider it plausible that functional variants to a level of identity of at least 90% could be identified and would be useful in the process defined. I therefore consider it plausible that the invention can be worked across the full scope of the claim.

The second issue was whether working the invention across the full scope of the claim (i.e. determining which of the polypeptides having greater than 90% identity would have the requisite activity) would be an undue burden.  Alternatively, would the skilled person be required to undertake a research programme in order to work the invention across the full scope of the claims?

In this regard, the applicant submitted that (see at [67]):
  1. 90% sequence homology limited by the structure-function relationship does not give rise to an interminable number of polypeptides, but is in fact a very limited set of polypeptides;
  2. armed with the previously unknown information provided by the specification – namely that a UGT from a non-native source is useful for mogroside synthesis, along with five specific polypeptides that can be used for this purpose – the only variable for the PSA to consider is which functional homologs of those polypeptides can also be used;
  3. sequencing the polypeptides to confirm they have at least 90% identity to the five specific polypeptides is a routine technique in the art;
  4. armed with the common general knowledge in the art, the PSA knows which amino acid changes are likely to retain the function of the polypeptide; and
  5. there is no undue burden involved, in the context of a technology where it is routine to produce/express and screen large numbers of polypeptides.
The Hearing Officer found these submissions persuasive, and concluded that the specification is clear enough and complete enough for the invention to be performed by a person skilled in the art (at [68]-[69]).

Conclusion – Sufficiency is a ‘Case-by-Case’ Proposition

It is commonplace for applicants to claim their inventions more broadly than the specific examples that may be provided in the patent specification.  This is not unreasonable – if an applicant were limited in scope to only particular disclosed embodiments of an invention, in many cases a competitor may have little difficulty in coming up with a variation that avoids infringement while nonetheless utilising the novel principles that comprise the true contribution to the art made by the invention.

There is a nexus, therefore, between the contribution of the invention, the disclosure of that contribution in the patent specification, and the breadth of the claims – which corresponds with the scope of the patentee’s right to exclude competitors from exploiting the invention.

What the skilled person (or team) already knows – the ‘common general knowledge’ in the art – is critical in determining what degree of disclosure is enough (as in ‘clear enough and complete enough’) to enable the invention to be performed across the full scope of the claims.  Where the ordinary skill and knowledge of the PSA is relatively low, a more detailed disclosure may be necessary to explain how to put the invention into effect without the need to undertake extensive and burdensome trials – i.e. a ‘research programme’ – as was the case in CSR.  However, in fields where the PSA is more highly skilled and knowledgeable – such as biotechnology – the path from specific examples disclosed in the specification to a range of embodiments across the full scope of broader claims may involve no more than the application of well-known principles and/or routine activity.

As the contrasting outcomes in CSR and Evolva demonstrate, assessment of enablement and sufficiency is very much dependent upon the nature of the invention, the scope of the claims, and the capabilities and knowledge of the relevant skilled person.  It is therefore something that must be determined on a case-by-case basis in light of all of the pertinent circumstances.  The Evolva decision provides useful guidance on how the Australian Patent Office is likely to approach the inquiry.


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