As the product or process description is a derivative of the laws of disclosure, as Pumfrey J further observed in Taylor v Ishida (Europe) Ltd  FSR 224 "The duties of all parties, both the professionals and of the parties themselves, in relation to a product description, are the same as they would be in relation to disclosure." Thus, as with disclosure, a party and its advisors must ensure that a product or process description is full and frank and include even than which is detrimental.
In yesterday's Judgment in Starsight Telecast & Ors (aka Rovi) v Virgin Media & Ors (aka Virgin)  EWHC 828 (Pat) Arnold J criticised Virgin for losing sight of this principle. He made two points in particular:
First, it is not correct (as is sometimes said) that a product or process description only needs to contain information at the same level of generality as the claims of the patent in suit. Instead it needs to contain information of at least the level of specificity of the claims, and often it will need to contain rather more detailed information than the claims. This is because, even if the claims are expressed in general terms, the issues on infringement often involve understanding precisely how the allegedly infringing product or process is constructed or functions.
Secondly, the accused infringer's lawyers often argue (as they did in this case) that until they know how the patentee is putting its case, or construing the claims, they do not know what is relevant or not for the purposes of the product or process description. This can lead to a circular response from the patentee that they cannot fully formulate the claim until they have full details of the accused product or process. Arnold J opined that "The defendant has the primary responsibility to provide full particulars of its product or process. Both parties have a duty to cooperate with the other. Sometimes this may require a degree of iteration. But, in general, I do not accept that it is legitimate for a defendant to seek to use a lack of clarity of the claimant’s case on infringement as an excuse for not providing proper particulars of its product or process."
The net effect of Virgin's failure to provide sufficient particulars in its product or process description was that there was an unexpected hiatus at the start of the trial while Virgin's witness was cross-examined for longer than anticipated on the product description, and a further day then was lost while Virgin provided certain further information. In his Judgment Arnold J is critical of Virgin for failing to provide in the product description sufficient details (and details which in some respects were wrong), but Rovi also did not escape criticism; he said "Rovi contributed to the debacle on day 1 of the trial [because most of the further information they sought related to an infringement case which Rovi then did not pursue]; but I think it is clear that this was mainly the responsibility of Virgin for not having provided proper PPDs at the outset or at least well before trial. To the extent that Virgin’s difficulty was caused by uncertainty as to what particulars to provide, this was substantially self-inflicted in that they failed to apply for an order requiring Rovi to serve a statement of case on infringement, or otherwise to seek directions from the court."
In the Taylor v Ishida case (referred to above) Pumfrey J ordered indemnity costs against the errant defendant. Although Virgin were overall winners in this case (Rovi's two patents were held to be invalid) it will be interesting to see how Arnold J's judicial wrath will manifest itself when it comes to deciding costs.
This case is a salutary reminder to all those preparing product or process descriptions of the obligations to provide full and sufficient details.