Disparaging patent specifications, or your fish can stinks

Patent specifications often contain a part that explains the perceived disadvantages of the state of the art. In the case of the German patent DE 43 32 545 for a tear-off lid of sheet metal for a can, filed in 1993, the specifications explain various alleged disadvantages of the invention according to EP 236 736.

The plaintiff produces fish cans according to EP 236 736 and took exception to the description of the technology in the German patent. He sued, and I am not pulling your leg, the patentee based on an unfair competition and general tort (Deliktsrecht) claim, demanding deletion of four allegedly incorrect and disparaging ("herabsetzend") statements from the (granted and published) German patent.

Both lower courts, after obtaining an expert opinion, concluded that the characterization of the disadvantages of the state of the art was indeed wrong, held for the plaintiff and demanded deletion of the incorrect statements about the prior art.

The German Federal Court (BGH) reversed (I ZR 46/07, 10 December 2009): The German Patent Act exclusively regulated under which circumstances a third party had a right that a patent application or a granted patent be amended or revoked. This excluded any claim on another legal basis, such as unfair competition or general tort law. The BGH saw one possible exception when the disparaging remarks in a patent (application) were wholly unrelated to the invention, but this was not the case here (hmmm, one can think of funny examples here... but none of them very realistic). Since patent law did not foresee a claim for amendment of an incorrect description of the (perceived disadvantages of) the state of the art, the claim had to fail. Which, the IPKat assumes, comes as a relief to German patent attorneys because it is one less thing to worry about - writing a patent application that withstands all attacks being hard enough as it is.