The plaintiff (or claimant), Merck & Co. Inc., is a pharmaceutical company incorporated in the United States. It owned patents in the U.S. and U. K. describing a way to make monosodium alendronate or MA. MA had proved useful in suppressing bone resorption. So many physicians worldwide were prescribing it to treat bone diseases such as osteoporosis that it may well be the most widely used treatment for that condition.
Generics (U.K.) Ltd. (the defendant) was in the business of supplying pharmaceutical products in the United Kingdom. At some point, it notified the plaintiff that it intended to market a medication in the U.K. in which MA made in India by a company called CIPLA would be the active ingredient.
It also furnished the plaintiff with a confidential explanation of the CIPLA process for making its product and gave the plaintiff a limited time to admit non-infringement under the U.K. patent. Absent such a concession, defendant assured plaintiff that it planned to go to court to obtain a declaration to that effect. Within the time limit, the plaintiff itself filed suit in the Chancery Division, an English court of first instance. The suit claimed infringement of claim 1 of its English Patent by the CIPLA method as depicted by the defendant. In effect, plaintiff urges that the CIPLA process appropriates the entire value of its invention. The Chancery Court, however, ends up dismissing plaintiff's claim.
Under the U. K. Patents Act of 1977 (the Act) and the European Patent Convention of 1973 (EPC) [13 I.L.M. 271(1974), 15 I.L.M. 5(1976)], the monopoly sought by a patentee clearly has to be comprehensible to the patent reader, the Court notes. The reader has to be able to define the limits of the prohibited field before he sets out to make a rival product or to install a competing process.
"A patent is a document written by the patentee for publication to the world at large and designed not only to set out clearly what the invention is but to describe the monopoly sought in unambiguous terms. It is supposed to be comprehensible to members of the relevant trade simply on reading." [¶ 34]
In the instant case, however, the notional reader of the Patent could not have been sure of the protective scope the plaintiff intended. For example, he would be uncertain whether that protection reached the use of any sulphonic acid in the manufacturing process as well as the methanesulfonic acid (MSA) specified in claim 1 of the Patent.