In Bloomberg Law Article, Steven Maslowski and Rachel Elsby Discuss Doctrine of Equivalents

Bloomberg Law has published the article “INSIGHT: Patent Disputes—Navigating the Tangential Relation Exception,” written by Akin Gump intellectual property practice head Steven Maslowski and counsel Rachel Elsby. The article examines two recent patent dispute rulings by the U.S. Court of Appeals for the Federal Circuit and the doctrine of equivalents, which has been “a popular topic recently in biotech/pharma cases” that have been decided there.

Maslowski and Elsby write that the doctrine “imposes liability for equivalents to patented technology that don’t literally infringe a patent’s claims.” Inventors who apply for a patent, they say, “are allowed to change claims to address an examiner’s concerns,” but the inventor cannot subsequently say, “that his or her claims broadly include similar products.” This prosecution history estoppel, “can provide accused infringers with a potent defense against claims asserted under the doctrine of equivalents.”

The recent Federal Circuit decisions, the authors write, prove “the importance of having an objectively identifiable reason for claim amendments that does not encompass the claimed equivalent.” As a result, they suggest that when claims are amended in prosecution, “it may be useful to provide a specific, but narrowly-tailored, basis for the amendment that tracks the rejection at issue.” They also advise litigants who are tasked with countering the tangential relation exception to focus their arguments “on drawing a connection between the alleged equivalent and the specific subject matter of the rejection that triggered the amendment.”

To read the full article, please click here.