May 13, 2022

Inventors, inventions, and the muddy metaphysics of patent law


Patent practitioners often grapple with the difficult question of who to name as an inventor in a patent application and, relatedly, what the inventive concept of the application actually is.

According to section 22 of the Patents Act 2013, a patent for an invention can only be granted to a person who is the inventor, derives title from the inventor, or is the personal representative of a deceased person who meets those two requirements.

Since the right to grant extends in all cases from the “inventor”, identifying the person or persons who qualify as an inventor can be crucial to the valid grant of rights. Perhaps unhelpfully, the Act simply defines “inventor” as “the actual deviser of the invention”1 leaving wide open the question of how to determine what qualifies as an “invention” and who qualifies as its inventor.

Matters become more complicated when multiple “inventors” are associated with technology described in the patent.  It is common for larger companies and research organisations to employ teams to work collectively on developing new technologies. Project leads can be under internal pressure to identify members as making a significant contribution to the conception and implementation of new concepts, especially in organisations which allocate the proceeds of commercialisation to inventors. External resources may be called upon to contribute in technically difficult and/or highly specialised areas. Yet, determining inventorship in joint collaborations has been described by one court as “one of the muddiest concepts in the muddy metaphysics of the patent law”.2

The right to grant under the Patents Act 2013 derives in all cases from the “inventor”.  Getting the inventor wrong could have fatal consequences to a granted patent. In Kennedy v Hazelton [1888] USSC 288; 128 US 667 (1888) it was held (at 672):

“The patent law makes it essential to the validity of a patent, that it shall be granted on the application, supported by the oath, of the original and first inventor, (or of his executor or administrator,) whether the patent is issued to him or to his assignee. A patent which is not supported by the oath of the inventor, but applied for by one who is not the inventor, is unauthorized by law, and void, and, whether taken out of the name of the applicant or of any assignee of his, confers no rights as against the public.”

Under s.114(1)(b) of the Patents Act 2013, a patent may be revoked if the patentee is not entitled to the patent. Revocation would seem to be the natural consequence of obtaining a granted patent without valid title from the inventor(s). Under s.114(1)(d) of the Patents Act 2014 a patent may be revoked if it was obtained by false suggestion or misrepresentation. That section could be enlivened if a Notice of Entitlement filed under s.73 misrepresents the applicant’s right to grant.


Similar provisions were considered in University of British Columbia v Conor Medsystems, Inc [2006] FCAFC 154 (31 October 2006) with the majority concluding that a patent was invalid if the patentee had not perfected title at the time of grant.


While the Act contains provisions to remedy defects3 (discussed later in this paper) these appear to be contingent on whether, as a matter of law, the patentee was entitled to the patent at the time of grant. A patentee with no valid title under agreement or at common law at the relevant date is likely to be left with no options to perfect title / correct the Register and the patent will be revoked as void.4


In the Full Court in Conor Medsystems, Bennett J dissented and said that the question of entitlement was to be determined at the time of determining invalidity primarily because of the language of the statute (“is entitled” not “was entitled”). The legislative response to the majority’s decision was to add s.22A to the Patents Act 1990.5 It could be said that the addition of s.22A was to confirm that Bennett J was correct as there was no change to s.15. Alternatively, it could be said that the absence of a s.22A equivalent shows that New Zealand law should be the same as pre-raising the bar Australian law. Even if Bennett J were followed in New Zealand, this still leaves lack of entitlement at the time of proceedings and there may be difficulties in perfecting entitlement so late in the day.


So, how do we decide who is an “inventor” and relatedly, what is the “invention”/”inventive concept” they have devised?

Claims based approach rejected

In Yeda Research and Development Company Limited v Rhone-Poulenc Rorer International Holdings Inc and Others [2007] UKHL 43 Lord Hoffman held (at 20):

“The inventor is defined in section 7(3) as “the actual deviser of the invention”. The word “actual” denotes a contrast with a deemed or pretended deviser of the invention; it means, as Laddie J said in University of Southampton’s Applications [2005] RPC 220, 234, the natural person6 who “came up with the inventive concept.” It is not enough that someone contributed to the claims, because they may include non-patentable integers derived from prior art: see Henry Brothers (Magherafelt) Ltd v Ministry of Defence [1997] RPC 693, 706; [1999] RPC 442. As Laddie J said in the University of Southampton case, the “contribution must be to the formulation of the inventive concept”. Deciding upon inventorship will therefore involve assessing the evidence adduced by the parties as to the nature of the inventive concept and who contributed to it. In some cases this may be quite complex because the inventive concept is a relationship of discontinuity between the claimed invention and the prior art. Inventors themselves will often not know exactly where it lies.

A claims-based approach to determining inventorship which has found favour in other jurisdictions (notably the US) was rejected by Lord Hoffman because the contribution to a claim may be “non-patentable integers derived from the prior art”. But does this mean that if the contribution of an “inventor” turns out not to be patentable, the efforts expended disqualify them from being named as an inventor? Respectfully, for reasons expanded on below, we think the answer must be no, since the nature of the enquiry should be on the work which is carried out as distinct from the subsequent question of whether the product of the work is, as a matter of law, patentable.

The issue is touched on in an earlier decision of Christopher Floyd QC, sitting as a Deputy Judge in Stanelco Fibre Optics v. Bioprogress (unrep. 1st October [2004] EWHC 2187 Ch) which similarly rejected a claims-based approach to inventorship (at 15):

“15. It is clear that a mechanistic, element by element approach to inventorship will not produce a fair result. If A discloses a new idea to B whose only suggestion is to paint it pink, B would not be a joint inventor of a patent for A’s product painted pink. That is because the additional feature does not really create a new inventive concept at all. The feature is merely a claim limitation, adequate to overcome a bare novelty objection, but having no substantial bearing on the inventive concept. Patent agents will frequently suggest claim limitations, but doing so does not make them joint inventors. Some stripping of a claim of its verbiage, may be necessary to determine the inventive concept, and consequently the inventor. But one must keep in mind that it is the inventive concept or concepts as put forward in the patent with which one is concerned, not their inventiveness in relation of the state of the art.” (our emphasis)

This statement was specifically endorsed by Lord Justice Jacob delivering the judgement of the UK Court of Appeal in Markem Corporation and Anor v Zipher Ltd [2005] EWCA Civ 267 (22 March 2005) at [103]. Lord Justice Jacob similarly rejected a claims-based approach to inventorship in that case as follows (at [100] and [101]):

100. So what then about s.8? Does “invention” there mean what is claimed or does the context otherwise require? We think it must have some more general meaning than what is in the claims. The most obvious reason for that is that s.8 applies to situations where there are no claims at all – indeed even prior to a patent application. And applications themselves are not required to have claims. The question of entitlement can therefore arise before any claims exist – and in principle must remain the same whatever claims later emerge. Moreover, as the Deputy Judge observed, it is often the practice of patent agents to put in first drafts which are wider than they expect to end up with so as to draw a wide search. As for the final claims in the patent as granted, their form and content will depend upon a number of individual factors – what has turned up in the prior art forcing reduction in scope, what subsidiary claims the patent agent has formulated based on the description and what monopoly is actually thought to be valuable (there is no point in claiming wider).
101. Accordingly we think one is driven to the conclusion that s.8 is referring essentially to information in the specification rather than the form of the claims. It would be handy if one could go by the claims, but one cannot. s. 8 calls for identification of information and the rights in it. Who contributed what and what rights if any they had in it lies at the heart of the inquiry, not what monopolies were actually claimed. (our emphasis)

From these cases it is clear that the relevant enquiry is “who contributed what” to the inventive concept. But what demarcates an inventive contribution from a non-inventive one in cases more nuanced than Christopher Floyd’s example of merely suggesting you paint something pink?

UWA v Gray: research vs invention

In University of Western Australia v Gray7 the Australian Federal Court was required to determine the ownership of an innovative way of treating cancer using microspheres developed by Dr Gray during the course of his full-time employment by UWA as a Professor of Surgery. Both the Federal Court, and Full Federal Court on appeal8, held that a duty to research did not carry with it a duty to invent and, absent an express provision in the employment agreement which imposed a duty to invent, Dr Gray was under no duty to account to UWA for any inventions, patents, or patent applications.

The decisions draw a distinction between “research” and “invention” on which the lower court said the following:

1422 The notion of the “inventive concept” is reflected in the judgment of Fletcher Moulton LJ in Hicton’s Patent Syndicate v Patents and Machine Improvements Co Ltd (1909) 26 RPC 339 in which he referred to Watt’s idea for the condensation of steam from which the steam engine was developed.  The following passage from the judgment was quoted with approval in National Research Development Corporation 102 CLR 252 (at 264):
“Now can it be suggested that it required any invention whatever to carry out that idea when once you have got it?  It could be done in a thousand ways and by any competent engineer, but the invention was in the idea and when he had once got that idea, the carrying out of it was perfectly easy.  To say that the conception may be meritorious and may involve invention and may be new and original, and simply because when you have once got the idea it is easy to carry it out, that that deprives it of the title of being a new invention according to our patent law, is, I think, an extremely dangerous principle and justified neither by reason nor authority.”
1426       The inventive concept marks a boundary between invention and verification.  An example arose in 1994 and 2002 in decisions reported in both the United States and Canada in relation to the use of the drug AZT to treat AIDS.  Glaxo/Wellcome had identified a new use for an old compound in conceiving the idea that AZT would work in humans against the HIV retro virus.  It used external scientists employed by the National Institutes of Health (NIH) to perform critical blind testing on the AZT and on other compounds (none of which were identified).  The NIH scientists found that the AZT did inhibit HIV replication and so advised.  The Glaxo/Wellcome patent was considered in the US Court of Appeals in Burroughs Wellcome Co v Barr Laboratories Inc (1994) 40 F 3d 1223.  The argument had been raised there that the patent was invalid because of the wrongful exclusion as inventors of the NIH scientists.  The argument focussed on when the inventors conceived the invention.  Burroughs Wellcome said it was before they learnt the results of the NIH tests.  The respondents argued that the NIH confirmation of the inventions operability from the NIH tests was an essential part of the inventive process.  The Court of Appeals held that the NIH scientists were not joint inventors.  It set out the following principles as established by US appellate courts:
  1. Conception is the touchstone of inventorship, the completion of the mental part of inventions.
  2. Conception is the “formation in the mind of the inventor of a definite and permanent idea of the complete and operative invention as it is hereafter to be applied in practice”. It is complete only when the idea is so clearly defined in the inventor’s mind that only ordinary skill would be necessary to reduce the invention to practice without extensive research or experimentation.
  3. An inventor need not know that the invention will work for conception to be complete. The inventor need only show that he or she had the idea.  The discovery that an invention actually works is part of its reduction to practice.
  4. It is not the law that the inventor’s definite and permanent idea must include a reasonable expectation that the invention will work for its intended purpose even when it deals with uncertain or experimental disciplines where the inventor cannot reasonably believe that an idea will be operable until some result supports that conclusion.

The propositions set out in Burroughs Wellcome (1994) 40 F 3 1223 define “invention” by reference to completion in concept which distinguishes the invention from its verification and reduction to practice.”

 So from these passages of University of Western Australia v Gray we understand that:

  1. Conception is the touchstone of inventorship.
  2. There is a difference between conceiving (inventing) and verifying (reducing to practice).
  3. An inventor need not know an invention will work for conception to have been completed, but
  4. Conception will be complete only when the idea is so clearly defined in the inventor’s mind that only ordinary skill would be necessary to reduce the invention to practice without extensive research or experimentation.

 “Ordinary skill” Brightline test proposed

The contention that someone who merely reduces to practice using ordinary skill an invention conceived by another finds support in a number of other cases. It is submitted that these cases also establish that the reverse is likely to be true – a member of a team who contributes more than ordinary skill to the task of reducing to practice an invention conceived by another will be an “inventor” for the purposes of patent protection – and this will remain the case even if their contribution is subsequently deemed to be unpatentable through lack of inventive step.

If correct this makes the enquiry into the nature of work conducted (ordinary skill or something more?) a useful Brightline for establishing inventorship. That test would involve two simple enquiries:

  1. Did a team member contribute to the inventive concept?
  2. If yes, is what they contributed to the inventive concept the product of more than ordinary skill?

Importantly, if extensive and/or prolonged research or experimentation are required to reduce the invention to practice, the enquiry into “inventorship” needs to be ongoing until the inventive concept is fully reduced to practice.

The veracity and application of the test can be Illustrated with reference to two case studies.

Case Study #1: Henry Brothers

Henry Brothers concerned a complicated claim and counter-claim for compensation for crown use of an invention relating to pre-fabricated blast-resistant buildings in Northern Ireland at a time when there was considerable unrest there. The names of witnesses were even anonymised for security reasons.

The Crown used an experienced civil engineer, Mr Z, to use the invention in the construction of a police station. Henry Brothers, which owned the patent, conceded that Mr Z was a joint inventor, and that the Crown was a co-owner of the patent, but sought compensation for the Crown’s use on the basis that the Crown’s rights as co-owner did not include engaging an independent contractor without its consent to grant the requisite license to exercise the patent rights. The Crown’s response was to apply for revocation on that basis that Mr Z was the sole inventor of the invention.

The invention is explained in the following extracts from the granted patent GB 2277334 B ‘Prefabricated blast resistant building structures’:

“This invention relates to prefabricated blast resistant building structures, and in particular prefabricated structures having at least two storeys.


Conventional building structures having two or more floors can suffer substantial blast damage even when subjected to bomb blast of low intensity. The floors of a conventional building structure …can withstand large loads in the downward vertical direction but are unable to resist sideways forces particularly those arising from bomb blast or mortar attacks.


It is the aim of the present invention to provide a prefabricated blast resistant building structure, especially one having two or more storeys, which limits relative movement between different parts of the structure by spreading the load exerted by the blast pressure over a greater part of the structure.


According to the present invention, there is provided a prefabricated blast resistant building structure, the structure comprising exterior walls constructed from a plurality of preformed panels, a roof, and an internal frame structure for supporting the roof and exterior walls, wherein key-joint means is provided at the boundary of at least some of the pre-formed panels of the exterior walls, which key-joint means is configured for limiting relative displacement between adjacent pre-formed panels in a direction perpendicular to the major plane of the panels thereby transferring shear forces from one panel to another to spread blast pressure over the structure in the event of a bomb blast.



Justice Jacob had found at first instance in the Patents County Court9 that the “key joint means” was central to the inventive concept of the patent at issue. On the facts, Mr. X, for Henry Brothers, had designed a two-plate shear joint.

Following tests conducted, and meetings attended, by Mr. X and Mr. Z in February and March 1993, Mr. Z developed a three-plate key joint.

Lord Justice Jacob concluded that Mr Z, was the sole inventor (at 706):

Henry Brothers appealed. On appeal it did not challenge Jacob J’s finding of primary facts, but challenged the legal conclusion which he drew from them. It submitted the court should identify the “inventive concept” of the claims, and on that approach Mr. X was seen to have contributed the whole of the inventive idea, except that his joint was not a key joint.

The Court of Appeal did not accept that argument, holding (at 448-449):

I agree that it is necessary for the court to identify the inventive concept, but I think that Mr Purvis’s formulation of his argument exposed its weakness. The exception to which he had to add – that Mr X’s joint was not a key-joint – goes to the heart of the inventive concept (so far as there was an inventive concept at all, and not just a fairly routine application of engineering skill)…


I cannot entirely agree with the judge’s approach in the passage of his judgment (at 706) which I have already set out. I am not inclined to think that the invention was “a combination” of elements. Mr Z saw Mr X’s drawing (at a meeting at which Mr X was not present) and replaced one type of joint (intended to produce a labyrinthine effect) with another type (a key-joint intended to produce distribution of blast pressure, including rebound pressure). Mr X’s drawing of the joint was not so much useless as directed to a different objective. Nevertheless, I feel no doubt that the judge was correct in his conclusion.”

What is interesting in this passage is the parenthesised disclaimer: “so far as there was an inventive concept at all, and not just a fairly routine application of engineering skill”. It supports the proposition that inventorship turns on the nature of the task being performed by the alleged inventor with respect to what has been identified as the “inventive concept” of the specification: and that these assessments (of firstly, work in relation to the inventive concept and, secondly, the nature of that work) might be given equal weighting so that neither:

  • A routine application of engineering skill in relation to the inventive concept; nor
  • A non-routine application of engineering skill on something other than the inventive concept; will qualify someone as an inventor / joint inventor.

Implicit in the finding of both Jacob J (and the UK Court of Appeal) that Mr Z was the inventor of the key joint, was the factual conclusion that not only did Mr Z work exclusively on the key joint but that Mr Z arrived at the key joint through the application of more than ordinary skill (or, in the words of the Court of Appeal, “a fairly routine application of engineering skill”). It is this effort which demarcates the act of invention from other non-relevant activities relating to the key joint. Likewise, Mr X was not an inventor because, although his efforts to develop the two-plate shear joint may have involved the exercise of more than ordinary skill, those efforts were directed to something both courts found was not the inventive concept of the patent.

Case Study #2: Polwood v Foxworth

The distinction between “invention” and the exercise or ordinary skill is more explicitly addressed in Polwood v Foxworth11. The case involved a dispute between two companies as to the entitlement to the grant of a patent12 which claimed:

“…a method for production of organic plant growth media from sawmill waste, said process comprising the steps of:-


introducing … sawmill waste into an inlet of a conveyor mechanism containing a body of heated water;


submerging said sawmill waste in said body of heated water for a predetermined period of time to kill microorganisms, … whilst transporting said treated sawmill waste towards an outlet of said conveyor mechanism;


and at least partially dewatering said treated sawmill waste to a predetermined moisture content.”

The patent was also directed to an apparatus for implementing the method of the invention. On the facts, a Mr. Rampton discussed with his neighbour, Mr. Connick, the idea of transporting material (bark) through processing equipment (two augers) which causes the plant material to be submerged in treated water. The resultant plant growth medium was then to be dewatered to reduce its moisture content. They formed Polwood and communicated the concept to Mr Power and Mr Kemp of Foxworth under a license. Using the information communicated Foxworth developed the concept by building prototypes and ultimately an apparatus to implement the concept.

At first instance13 the trial judge concluded that Polwood and Foxworth were joint inventors: Polwood of the method and Foxworth of the apparatus. Polwood appealed, contending that there was a single invention the subject of the patent and that is the concept, which it said encompassed both the method, apparatus, and product claims. Polwood recognised that Foxworth first made the apparatus but contended that this was no more than implementing the completed and final Polwood concept. Although not phrased as such this is essentially a submission that Foxworth’s contribution was limited to reduction to practice without extensive experimentation or research per UWA v Gray. The Full Federal Court disagreed:

21 The primary judge determined inventorship by reference to the ‘inventive concept’ of the patent application. In terms of the approach in the United Kingdom, his Honour’s conclusion is to the effect that the invention had two ‘hearts’. His Honour did not conclude from the evidence that Foxworth simply acted on Polwood’s instructions. His Honour did not conclude that Foxworth merely provided its skill to implement Polwood’s concept or that it carried out its work under Polwood’s instructions. The primary judge clearly found that Foxworth contributed to the inventive concept of the second ‘heart’ and not merely skill but ‘inventive skill’ (at [215]). His Honour held at [215] that the design and manufacture of the apparatus involved inventive merit. It was not a case of adding common general knowledge to Polwood’s inventive concept. (my emphasis)
The Full Court’s assessment of the decision at first instance highlights factual findings of the primary judge that Foxworth’s contribution was inventive skill, and not simply adding common general knowledge to a concept already developed by Polwood. This is tantamount to a factual finding that Foxworth both worked on the apparatus and exercised more than ordinary skill in doing so. Putting this another way, in UWA v Gray it was held that conception will be complete only when the idea is so clearly defined in the inventor’s mind that only ordinary skill would be necessary to reduce the invention to practice without extensive research or experimentation. Here the finding was that inventive skill was needed to reduce the apparatus to practice – so Polwood’s conception of this aspect of the inventive concept was incomplete and Foxworth is an inventor.
In conducting its own assessment the Full Federal Court looked to overseas jurisprudence on indications of joint inventorship – notably from the UK and US. It held (our emphasis):
34 The entitlement to the grant of a patent as the inventor is not determined by quantitative contribution. The role of joint inventors does not have to have been equal; it is qualitative rather than quantitative. It may involve joint contribution or independent contributions. The issue is whether the contribution was to the invention. What constitutes the invention can be determined from the particular patent specification which includes the claims. In some cases, evidence can assist. In some cases, the reduction of a concept to a working apparatus by a person may not be part of the invention, in other cases it may be. For example, the construction of an apparatus may involve no more than carrying out the instructions in the specification. This would not normally entitle that person to joint inventorship. On the other hand joint inventorship may arise where the invention is in the apparatus itself, or where the person constructing the apparatus contributed to a different or better working of it which is then described and claimed.
35 One criterion for inventorship may be to determine whether the person’s contribution had a material effect on the final invention. It may be that an invention is made as part of a collaborative effort. In those circumstances, it would ordinarily follow that the collaborators are joint inventors of the product of the collaboration. In the present case, the subject of the patent application was not part of a continuing collaboration recognised as such by the parties.
36 To ascertain the inventor for the purposes of entitlement to the grant of the patent it is therefore necessary to determine the contributions to the invention described in the patent application. The claims may assist in that determination, bearing in mind that the claims may be to less than the totality of the invention. It may also be appropriate to investigate the contributions to the inventive steps giving rise to the invention.

The Full Court continued:

40 In Stanelco Fibreoptics Ltd’s Applications [2005] RPC 15 (at [15A]) Mr Floyd QC said that ‘a mechanistic, element by element approach to inventorship will not produce a fair result’. He was of the view (at [18]) that the basic enquiry is to determine the actual deviser(s) of the inventive concept. However, he linked that principle with what is put forward in the patent as inventive. He also agreed with Judge Fysh QC in Markem Corp v Zipher Ltd (No 1) [2004] RPC 10 at [66]–[71] where his Honour observed that the purveyor of a non-inventive contribution to a working combination may be a co-inventor and that the quality of the contribution and the impact on the result depends on the facts in each case. It is not necessarily the inventiveness of the contribution that is the determining factor. The important question is whether the second researcher can be said in substance to be jointly responsible for devising the inventive concept of the patent (Stanelco at [20]).

The Full Court went on to adopt with approval a number of propositions drawn from UK and US jurisprudence. In each of these there is a reference to the nature of the contribution requiring more than simply the exercise of ordinary skill (our emphasis):

44 In IDA the Court of Appeal revisited the subject and repeated what had been said in Henry Brothers and Markem [2005]. There, the Court concluded at [31] that the fact the first person did not know whether or how his idea would work did not prevent him from being the sole devisor of the invention. Finding out whether or not it worked was, in that case, a matter of simple and routine experimentation or mere verification (at [32]). It ‘amounted to no more than adding the common general knowledge in the art’ (at [35]). Lord Justice Jacob, with whom Wilson and Ward LJJ agreed, observed at [37] that normally the addition of matter which is common general knowledge often forms the subject of subsidiary claims of no significance as regards inventorship and may go to ‘the generality of the main concept’. At [43] Jacob LJ warned against dividing the information into ‘a myriad of sub-concepts’, bearing in mind that a patent is only meant to have one inventive concept. These observations (at [38]) were clearly directed to a case where what was needed to get a patent was only the disclosure of an idea. In that case, disclosure of a means of enablement was not necessary and the skilled person could readily practice the invention. On the other hand, in Norris’s Patent [1988] RPC 8 Falconer J considered a patent with claims to the method of use and to the apparatus itself, which constituted two distinct but interrelated aspects of the invention.
45 As Laddie J had noted in University of Southampton’s Applications [2004] EWHC 2107; [2005] RPC 11 (at [46]) (cited with approval by Lord Hoffman in Synthon BV v SmithKline Beecham [2005] 235 All ER (D) at [28] and by Jacob LJ in IDA at [38]), devising an invention and providing enabling disclosure may both be necessary to secure valid patent protection but they relate to different aspects of patent law. This was elaborated by Jacob LJ in IDA at [39]:

In the context of entitlement to a patent a mere, non-enabling idea, is probably not enough to give the patent for it to solely the devisor. Those who contribute enough information by way of necessary enablement to make the idea patentable would count as “actual devisors”, having turned what was “airy-fairy” into that which is practical…On the other hand those who contribute no more than essentially unnecessary detail cannot on any view count “s “actual devisors”.

46 This approach is similar in concept to that adopted in the United States. In Gunter v Stream 573 F.2d 77 (1978), in the context of interference proceedings, Baldwin J, citing Mergenthaler v Scudder 11 App. DC 264 (1897) described ‘conception’ of the invention as the complete performance of the mental part of the inventive act; the formation in the mind of the inventor of a definite and permanent idea of the complete and operative invention, as it is thereafter to be applied in practice. The mental part of the inventive act is then complete. What remains belongs to the department of construction, not invention (at 80). While conception can be complete although experimentation may continue, conception is complete when one of ordinary skill in the art could construct the apparatus without unduly extensive research or experimentation (Trovan Ltd v Sokymat SA [2002] USCAFED 164; 299 F.3d 1292 (2002), Sewall v Walters [1994] USCAFED 426; 21 F.3d 411 (1994) at 416; Burroughs Wellcome at [5,6]). As was observed in Burroughs Wellcome, conception is complete when the inventor has some particular solution to the problem at hand, the operative invention, although it is not necessary to know that the invention will work (at [7,8]). A distinction can be drawn where the first person would have been able to give effect to the idea but utilised the expertise of another to put the effect into practice, under instruction (Mueller Brass Co v Reading Industries Inc 352 F. Supp. 1357 (1972) at [16,17]). However, general goals or a research plan to be pursued are not sufficient. In Mueller inventorship was regarded as a role in the final conception of that which is sought to be patented. It is clear that, in working out the inventive concept in a patent, each patent will be different and it will be necessary to ascertain the inventive concept from the whole of the specification. Contribution after the invention was fully conceived where that contribution was under the direction of the inventor does not give rise to entitlement to the invention. A person must be able to say that without his or her contribution to the final conception it would have been less (Mueller at [16,17]). As Newcomer J observed at [16,17] ‘the exact parameters of what constitutes joint inventorship are quite difficult to define. It is one of the muddiest concepts in the muddy metaphysics of the patent law’. While the law regarding inventors may be affected by the ‘first to invent’ aspects of the patent law of the United States, the philosophy is apt.
51 In Finkelstein v Mardkha 518 F.Supp.2d 609 (2007) Holwell J (at [6]) referred to Burroughs Wellcome and noted that conception will not yet be complete where extensive research and experimentation is still required to reduce an invention to practice. Justice Holwell stated that, ‘while research and experimentation, especially if extensive, may be sufficient to render one a co-inventor, exercising ordinary skill in the art, even if extensive, is not’ (quoting Sewall at 416). The proper inquiry ‘concerns the quality, not the quantity of the contribution’.

This analysis complete, the Full Court then considered Australian jurisprudence on joint inventorship14 before summarising the enquiry on appeal (and explicitly adopting the proposition advanced above) as follows:

56 The primary judge did not directly consider whether the concept was sufficient to enable the apparatus as described and claimed to be designed and built by the application of common general knowledge or ordinary skill. That was not an issue before his Honour. This gives rise to some difficulties with the matters presented to this Court….

Difficulties noted, the Full Court was satisfied that Foxworth’s contribution was more than the application of common general knowledge to Polworth’s concept:

60 However, while the primary judge was not asked to and did not make the specific findings, his Honour found that Foxworth contributed inventive skill in its design and construction of the PSU/Mark II (at [215]). That apparatus was as described and claimed in the patent application. His Honour also found that Foxworth was ‘the inventor’ of the apparatus (at [259]). Those conclusions suggest that his Honour’s view was that Foxworth made a material, inventive contribution to the inventive concept of the patent application. His Honour found that the Polwood concept was an inventive concept. He did not say that it was the inventive concept.

These findings confirm the ordinary skill Brightline test as both applicable and correct. Under that test Foxworth was an inventor because its contribution:

• Was to “an” inventive concept (described in the patent); and
• Involved more than the application of CGK / ordinary skill.

Other cases

In its analysis of Australian jurisprudence the Full Court in Polwood v Foxworth adopted15 from JMVB Enterprises Pty Ltd v Camoflag Pty Ltd Ltd [2005] FCA 1474; (2005) 67 IPR 68 a statement from Crennan J at [132] that rights in an invention are determined by objectively assessing contributions to the invention rather than assessing the inventiveness of respective contributions. As advanced above, this is entirely consistent with the statement in Stanelco that “the purveyor of a non-inventive contribution to a working combination may be a co-inventor and that the quality of the contribution and the impact on the result depends on the facts in each case. It is not necessarily the inventiveness of the contribution that is the determining factor.”

The Full Court also cited with approval (at [46]) Yeda Research and Development Co Ltd v Rhone-Poulenc Rorer International Holdings (2008) I All ER 425 in the context of a discussion about whether a claims-based approach to inventorship is appropriate. In Yeda Lord Hoffman also applied the distinction between “invention” and the mere exercise of common general knowledge as follows (at [60])

60. In the present case it is possible-I express no view at all about it, since it would be wholly premature to do so-that the fact-finding tribunal may in due course find that Professor Schlessinger, in providing the antibody for the purposes of the tests, did no more than provide the equivalent of “common general knowledge in the art” and (despite the statutory presumption) did not contribute to the inventive concept of the claimed invention. If that were to happen he would not be the inventor, or a co-inventor, within section 7(2)(a), and any alleged breach of confidence would be strictly irrelevant to the entitlement claim. (our emphasis)

The statement of the Full Court in Polwood v Foxworth in paragraph 40 (set out above), and the cases relied upon by the Full Court to reach the view that Foxworth was an inventor, in our view support the proposition that the focus of the enquiry as to whether a contribution is “inventive” turns on the nature of the task conducted and not the legal result (ie conferring an inventive step from a patentability perspective) and is a two stage enquiry looking at:

1. Whether the contribution was to the inventive concept; and
2. Whether the contribution was qualitatively significant (in the sense of involving the exercise or more than ordinary skill).

If correct, it means that a non-inventive contribution to the “inventive concept” produced by the exercise of something other than common general knowledge / ordinary skill should give rise to a claim to joint inventorship.


Think about that: if correct it means that inventors don’t need to be inventive from a patentability perspective. This is a proposition which many IP professionals may find difficult to reconcile but the following scenario illustrates how that can occur:


• A first person at Blue Sky Innovations has the idea of improving Product A by adding features B + C.
• A second person at Blue Sky Innovations tasked with getting A + B + C to work, finds that it is necessary to add feature D to do so.
• A patent is granted to Blue Sky Innovations for the working concept of A + B + C +D.
• The validity of the patent is challenged on the basis of a prior art document published just before the patent was filed. The prior art shows a modification of Product A by adding features B + D to form A + B + D. Evidence proves that C was common general knowledge but fails to show that either B or D were common general knowledge.
• The validity challenge is successful on the basis that it would have been obvious to add the common general knowledge C to prior art A + B + D.

It will be observed that there is no finding in this scenario that D conferred an inventive step in this case because it was already known from the prior art. However, since it wasn’t common general knowledge to add feature D, the second person was properly named as an inventor.


The ordinary skill Brightline remains consistent with, but preferable to, the conclusion in UWA v Gray that:
• inventors are those who conceived the invention, and
• conception is complete only where extensive research or experimentation are not required to reduce it to practice,
because, as noted above, for some inventions it may not be possible to determine if extensive research or experimentation are required until after the reduction to practice has been performed. This means that the enquiry into “inventorship” according to UWA v Gray is in many cases going to be a hindsight enquiry possible only after the invention has been commercialised. Focussing on contributions minimises that difficulty.


Remedies and advice


A patentee with valid title by way of agreement or operation of law at grant has various means to correct the Register to add or remove inventors so that the Register accurately reflects the actual devisors of the invention. Patent specifications can be amended by the Commissioner or the Court under ss.83 and 89 of the Act. However, since the forms on which inventors are named do not form part of the specification, the more relevant provisions are ss.202 and 203 of the Act which provide:


202 Commissioner may correct other persons’ mistakes in patents register, etc
(1) The Commissioner may (on application by any person or on the Commissioner’s own initiative) correct an error or omission that the Commissioner is satisfied has been made by any person in—

(a) the patents register; or
(b) any patent; or
(c) any patent application; or
(d) any documents filed in connection with a patent application or filed in proceedings before the Commissioner in connection with a patent or patent application.

(2) Any person (whether or not that person made the error or omission) may apply for a correction under this section in the prescribed manner.


203 Court may rectify patents register
(1) The court may, on application of any person aggrieved, order the patents register to be rectified by making an entry, or varying or deleting an entry, in it.


However, a patentee with no valid title under an agreement or at common law at grant is likely to be left with no options to perfect title / correct the Register and the patent will be revoked as void. Those involved with securing patent rights should therefore take steps as early as possible to:

• Understand the “inventive concept”
• Identify the full team associated with conceiving and developing that inventive concept
• Identify the nature of contribution of those team members, and
• Obtain assignments from those team members who exercised more than ordinary skill with respect to the inventive concept identified

Critically the terms of reference of this enquiry should focus on the nature of the work. IP professionals will need to set aside any prejudices they may bring to the task as to the “value” of a team member’s contribution.

In New Zealand it would also be prudent to err on the side of treating team members as “inventors” for assignment and identification purposes. In a section dealing with requests for parties to be entered on the patent Register as an inventor, the British Manual of Office Practice (Patents) specifically confirms that mere mention does not equate to a legal conclusion as to its correctness:


“Requesting Mention [as inventor]
16,3 Such mention is for information only, and has no effect on the rights of any person under the patent, nor is it incompatible with some other person being treated as the true and first inventor for any other purpose under the Act”.

This suggests that there will be no adverse consequence to naming someone as an inventor incorrectly in New Zealand. The reverse may not be true.





[1] Section 5 Patents Act 2013


[2] Mueller Brass Co v Reading Industries Inc 352 F Supp 1357 (ED Pa 1972) at 1372.


[3] Including, potentially, application to the Commissioner under s.83 to amend the specification after acceptance, application to the Court under s.89 to amend the specification after acceptance, application under s.129 for substitution of applicants (which must occur before grant), and application to the Commissioner (under s.202) or Court (under s.203) to correct a mistake in the patent register.


[4] Although outside the scope of this paper, the passage from Kennedy v Hazelton would appear to be particularly apposite for applications made under the Patents Act 1953 for which applicants need to establish a right to apply not a right to grant.


[5] Which reads “22A Validity not affected by who patent is granted to

A patent is not invalid merely because:

(a)  the patent, or a share in the patent, was granted to a person who was not entitled to it; or

(b)  the patent, or a share in the patent, was not granted to a person who was entitled to it.


[6] As an aside, the reference here to “natural person” would seem to exclude AI from the category of people who can qualify as “inventors”, suggesting that the offices on both sides of the Tasman got it right when rejecting a patent application naming AI as an inventor in recent cases: see Stephen L. Thaler [2022] NZIPOPAT 2 and Commissioner of Patents v Thaler [2022] FCAFC 62


[7] University of Western Australia v Gray [2008] FCA 498


[8] University of Western Australia v Gray [2009] FCAFC 116, (2009) 179 FCR 346.


[9] [1997] RPC 693 (Jacob J.)


[10] Henry Brothers (Magherafelt) Ltd v Ministry of Defence and Norther Ireland Office [1999] RPC 442


[11] Polwood Pty Ltd v Foxworth Pty Ltd (includes corrigendum dated 5 March 2008) [2008] FCAFC 9 (18 February 2008)


[12] AU 2010227018


[13] Foxworth Pty Ltd v Polwood Pty Ltd [2006] QSC 185


[14] Discussed briefly below.


[15] At [54]

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