Merck’s Singular Patent to be Reexamined

Scott Daniels | May 20, 2009

The Patent Office has granted reexamination on Merck’s U.S. Patent No. 5,565,473 which covers its extremely successful allergy drug SINGULAIR. Sales of the drug are said to total about $4 billion per year.

The Patent Office concluded that each of seven prior art references cited in the Reexamination Request “raises a substantial new question of patentability as to claims 1, 7 and 18-22 of the ‘473 patent. One of the references was cited during the original ‘473 prosecution, but the others were not.

The Request for Reexamination was filed, not by Teva, but by Article One Partners. Article One styles itself as “a global online community working to legitimize the validity of patents.” It conducts contests by soliciting the public for prior art references against specific patents and then awarding substantial cash prizes to those who submit references that, in the opinion of Article One, renders one of the patents invalid.

The ‘473 patent is currently being litigated in Merck v. Teva (Civ. Act. No. 07-1596) in New Jersey. The parties completed a bench trial in February on the issues of obviousness and inequitable conduct, and are now awaiting a ruling from the court.

One of the references cited in the reexamination grant the “Young 89’ Article” was relied upon Teva for its assertion at trial that the ‘473 patent was unenforceable because of inequitable conduct by Merck.

The request was filed April 27, 2009.


Shortly after the announcement that reexamination of the ‘473 patent had been granted, counsel for Teva informed the trial judge, noting the PTO’s determination that “[t]here is a substantial likelihood that a reasonable examiner would consider [Young 89] important in deciding whether or not claims 1, 7 and 18-22 are patentable.” According to counsel for Teva, the PTO’s grant of reexamination “is relevant to the defense of inequitable conduct.”

Three days later, counsel for Merck replied that reexamination grant was not significant – that the PTO grants 95% of all requests and that the issues raised in reexamination differ from those before the court.

This case demonstrates the potential impact of reexaminations on pending litigation.

Subscribe | 登録


Recent Posts



  • dictionary
  • dictionary
  • 英語から日本語

Double click on any word on the page or type a word:

Powered by