An inventorship dispute of Cooke v Watermist under appeal at the High Court has proven the advantage of being the registered, assumed inventor. The case is also a wake-up call for those that disregard documenting the innovation process.

The patent in suit, GB 2458698 granted to Watermist Ltd., covered a hose reel unit comprising a motor to allow creation of a mist for suffocating a fire. Mr. Cooke pleaded co-inventorship with the registered inventor, Mr. Bridgman. While providing as witness an account of the innovation process, his evidence and closing submissions to the UKIPO were however directed to his being sole inventor. On the other hand, Mr. Bridgman’s evidence amounted to little more than “I came up with the idea… He said he did and that is not the truth. It is as simple as that”.

The UKIPO hearing officer followed principles derived from an earlier case, specifically that the first step is to decide who is/are the inventor(s), i.e. actual deviser as defined in S. 7(3) of The Patents Act, and only then to consider whether someone else may be entitled to be added as sole/joint inventor. The ‘actual deviser’ is considered to be the person(s) who “came up with the inventive concept” of the application. Since the deviser is thus not necessarily a person who contributed to any feature(s) of the claims, the nature of the inventive concept of the application must be assessed, and then who contributed to it. Furthermore, a person who seeks to be added as a joint inventor bears the burden of proving that he contributed to the inventive concept underlying the claimed invention. Still more onerous, a person who seeks to be substitute the registered sole inventor bears the burden of proving that: (i) he devised the inventive concept; and (ii) the registered inventor did not even contribute to the inventive concept.

No documentary evidence was adduced by any party. Consequently, the hearing office considered in detail the credibility of all witnesses.

The hearing officer assessed Mr. Cook’s credibility as poor, describing his evidence as “evasive … inconsistent … selective” and considering for example misleading signing of letters as “Operations Director” to avoid being perceived as, in Mr. Cookes’ own words, “some Herbert in the workshop”. Furthermore, the hearing officer noted that Mr. Cooke had not raised the issue of his entitlement until after he had been informed that he may be infringing the patent.

Mr. Bridgman on the other hand, was described as “nervous” and “imprecise”. The hearing officer also noted that Mr. Bridgman’s written and oral evidence gave no indication as to how he came to arrive at the invention.

Refreshingly, a third party, Mr. Killaspy, owner of the commercial supplier (‘Fireworks’) of the hose reel systems and who shared an interest in Watermist with Mr Bridgman, was deemed a “generally reliable witness”. Nevertheless, confusion remained in Mr. Killaspy’s accounts as to whether or not a phone call from Mr. Bridgman concerned realising that an earlier prototype overhead misting unit designed by Mr. Cooke might be relevant to a particular commercial application (so providing inspiration for the patented hose reel system), or concerned the raw idea of putting the pump and motor in the housing.

In conclusion, the hearing officer stated that “where there is no documentary evidence, credibility is crucial”. Mssrs. Cooke and Bridgman were lacking equally in this respect, the evidence available from Mr. Killaspy further contributing to a finding that the burden of proof was not met by Mr. Cooke.

In the appeal, the Court agreed that the hearing officer was correct to use the burden of proof as last resort, and held that the hearing officer’s finding of primary fact based on the assessment of witnesses at first hand should not be overturned.

Given the lack of documentary evidence, the hearing officer was correct that what mattered was the relative credibility of Mr. Cooke and Mr. Bridgman, and to take into account Mr. Cooke’s delay in making his inventorship claim. Hence, the appeal was dismissed.

Here are some lessons for applicants and inventors that can be drawn from this case:

  • Agree inventorship, and ensure the correct inventor(s) is registered, from the start - when people are collaborating and the sums at stake are not necessarily large;
  • Document the innovation process and retain your records;
  • Get written, signed agreements in place before or soon after filing and keep them;
  • The test for (joint) inventorship is different in different countries: involve your advisor if you have any doubts;
  • Think twice before getting involved in an inventorship dispute: they can be acrimonious and personally stressful.