Patents

Case Note PCME v Goyen Controls

Jane Lambert

April 1999

This article previously appeared on the Lancaster Buildings  website

The first two conditions for the grant of a patent are that it is new and that it involves an inventive step (ss. 1 (1) (a) and 1 (1) (b) of the Patents Act 1977 respectively). An invention shall be taken to be new if it does not form part of the "state of the art" (s. 2 (1)).

The State of the Art

The "state of the art" in the case of an invention shall be taken to comprise all matter (whether a product, a process or anything else) which has at any time before the priority date of that invention been made available to the public whether in the United Kingdom or elsewhere by written or oral description, by use or in any other way (s. 2 (2)).

Distinction between Anticipation and Obviousness

An invention shall be taken to involve an "inventive step" if it is not obvious to a person skilled in the art, having regard to any matter which forms part of the state of the art in the foregoing definition (s. 3). Lack of novelty and lack of inventiveness are often run together either in an application for revocation or as a defence to a patent infringement action. The distinction between the two concepts is not always clear. The Australian judge Windeyer J helpfully suggested the following test in Sunbeam Corporation v Morphy-Richards (Aust) Pty Ltd. (1961) 180 CLR 98, 111. When want of novelty is alleged the thing or process claimed may be the product of inventive faculties but it is not an invention because it has already been disclosed to the public. When lack of inventiveness is alleged the thing or process may be new but is not really an invention in the sense of being a product of such inventive faculties. The following judgment illustrates how those issues should be analysed.

The Facts

This was an action for infringement and a counterclaim for revocation of a patent. The patent ("Rigby") had been granted to PCME Ltd. ("PCME") for a device that monitored the particle content of chimney emissions. It worked on a known principle that charged particles in a gas stream induce an inverse charge in an electrode which will grow as particles approach and diminish as they pass by. PCME claimed that Rigby produced a more accurate reading than previous devices in that it measured only the alternating component of the induced charge, thus eliminating such variables as humidity and temperature which could affect the signal. The defendant, Goyen Controls Ltd ("Goyen") sold a device called an "EMS4" which also measured emissions. PCME contended that EMS4 had infringed its patent and Goyen replied that the patent was invalid by reason of prior use or obviousness.

The Issues

The case turned on the validity of PCME's patent. Goyen argued that a system made by the Australian company, Blasto Industries Pty Ltd. ("Blasto"), before the priority date of the 30 April 1992 had anticipated PCME's invention. Alternatively, it contended that PCME's invention would have been obvious in the light of Blasto. Blasto's system consisted of a probe inserted into a gas stream to detect particle movement. Four issues therefore fell to be determined by Laddie J:

	whether Blasto's device and literature were used publicly prior to the priority date;
	if it was, what did such prior use disclose to those skilled in the art;
	whether such disclosure amounted to anticipation; or
	whether such disclosure rendered Rigby obvious.

Whether there had been Prior Use

His lordship accepted evidence that Blasto had started to manufacture its probe by February 1992, that it had sold some in March and April and that it had made deliveries before the priority date.

What was the Extent of the Disclosure

As prior use does not of itself invalidate a patent, the crucial question was what if anything was made available to those skilled in the art. Blasto's literature did not describe in any detail how the circuitry of the device operated and the device itself was a ‘black box’. To prevent competitors from copying its products, Blasto had embedded its circuitry in resin. A customer would not have been able to dismantle the device physically. The guidance of the Enlarged Board of the European Patent Office was that:

"Where it is possible for the skilled person to discover the... internal structure of the product and to reproduce it without undue burden, then both the product and its... internal structure become state of the art.... It is the fact that direct and unambiguous access to some particular information is possible, which makes the latter available, whether or not there is any reason for looking at it."

Goyen's expert had testified that he could have deduced how the Blasto device operated by non-destructive analysis. He said that it would have been easy to discern by testing that the device was a.c. coupled which meant that it must have been measuring or responding to the a.c. component in the signal produced by Blasto's probe. PCME argued that the skilled addressee would not have carried out the tests suggested by Goyen's expert because he would not have had the abilities of a skilled forensic engineer. Laddie J rejected that contention on the ground that the skilled addressee could have included a team and that team could have included a forensic engineer. His reasoning was founded on policy:

"Were it otherwise, in some cases it would be possible to re-patent information which any competent forensic engineer would be able to find out by obvious analytical techniques. Similarly where an ordinary skilled man in the art of making particular types of chemical products has no experience of reverse engineering, it would be possible in some cases to patent information about a commercially available product which was deducible by a competent but uninventive forensic chemist. I do not think that is the law."

What constitutes an Enabling Disclosure

In his lordship's view, the following questions arise when a product is made available to the public:

	what tests or analyses would it be obvious to carry out on the product,
	what would be the result of those tests, and how would those results be interpreted by the man skilled in the art.

PCME had argued that only information unambiguously obtainable from an examination of a black box should count as part of the prior art. His lordship rejected that argument. The ambiguity of information does not mean that it should be ignored. The fact that it may be inconclusive does not mean that it is not made available to the public. If the statement "it is probably A but may be B" is found in a document it is no less published than the statement "it is definitely A". If the information deducible is imprecise, it may affect whether it is sufficient to support anticipation (that is to say, lack of novelty) but it does not mean that it is to be treated as not published. Furthermore, it may well render a patent claim obvious.

Anticipation

After analysing Blasto's literature and considering the expert evidence the judge concluded that Blasto would have infringed the two main claims of the Rigby patent and decided that it had anticipated them.

Obviousness

Even if he had reached a different conclusion on novelty, the judge would have held that there was no inventive step. He had no doubt that a skilled addressee interested in making a competing product would have tried to improve on the Blasto probe. In relation to the type of circuit to be used, it would have been obvious to try to use the same type of circuitry as used by Blasto, namely an a.c. coupled amplifier and that would have fallen within the claims of Rigby. On that basis, his lordship dismissed the claim and allowed the counterclaim.

Application to Breach of Confidence

The question whether the sale of a black box or chemical preparation discloses its manner of construction or formulation to the public arises frequently in breach of confidence actions. It is submitted that Laddie J's approach as to whether or not the sale of a product forms part of the prior art could apply equally well to deciding whether or not its sale to the public places it in the public domain.

 

 

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