In 1996, the law governing the term of a U.S. patent changed. Today, a patent expires twenty (20) years from the date of filing of the corresponding patent application. For patent applications filed under the old law, the applicants may elect a term extending seventeen (17) years from the date of issue of the patent. The perceptive reader will have noted that, under the old law, time spent in prosecution was not deducted from the term of the patent. Thus, if the prosecution of the patent application could be prolonged, the resulting patent would issue later and would expire later. Sorry to say, some applicants seized upon and utilized this very ploy. Not unreasonably, parties accused of infringing these extended patents argue that such conduct is “inequitable” and that it renders the patent so prosecuted unenforceable. (Cancer Research Technology Ltd. v. Barr Laboratories Inc. et al.)
Cancer Research is the holder of a patent directed to a treatment for certain types of cancer. The patent, which issued in November 1993, is based upon an application filed in August 1982. It will expire in February 2014, more than thirty-three (33) years after the original application was filed. This amazing life span was accomplished through a process of repeatedly filing, abandoning and refiling continuation applications – in all, eleven (11) continuation applications and ten (10) abandonments.
When sued for infringement by Cancer Research, Barr argued that the patent was unenforceable due to “prosecution laches,” i.e. that it issued after an “unreasonable and unexplained delay in prosecution.” While there are very few cases where a patent has been found to be unenforceable due to prosecution laches, this is one of them. The Court found that the patent applicants’ claimed justification for the delay was not “objectively reasonable” in view of the fact that it had “never attempted to traverse (patentspeak for “argue against”) the (examiner’s) rejections.”
The patented drug, trade name TEMODAR, has annual sales of almost $370M. Not surprisingly, Merck & Co., Inc., the exclusive licensee of the patent, has vowed to appeal.
THE LESSON TO BE LEARNED: Don’t try to game the system.