3M, Ivoclar Vivadent Sue Each Other Over Tooth-Filler Patent

(Updates with excerpt from court documents in third paragraph.)

Dec. 1 (Bloomberg) -- 3M Co., the maker of Scotch Tape and Post-It Notes, was sued by Ivoclar Vivadent AG in federal court in Delaware for infringing a 1999 U.S. patent for material used to fill and restore teeth.

Today’s lawsuit came in the wake of an action 3M filed in Minneapolis yesterday against Ivoclar, asking a judge to declare it doesn’t infringe the Ivoclar patent.

In the Delaware complaint, Schaan, Liechtenstein-based Ivoclar contends 3M is violating the patent through sale of its “Filtek” line of dental-repair materials.

“3M had constructive and actual knowledge of the patent and the inventions embodied therein” before marketing the products, plaintiffs’ lawyers said in court papers, which seek a jury trial, royalties and triple damages, as well as an injunction to stop the infringement.

In the Minneapolis suit, St. Paul, Minnesota-based 3M seeks a jury trial and contends the patent isn’t valid.

“We’re looking forward to a speedy resolution by the Minnesota court,” Donna Fleming Runyon, a 3M spokeswoman, said in a phone interview.

The Delaware case is Ivoclar Vivadent AG v. 3M Co., 11- cv-1183, U.S. District Court, District of Delaware (Wilmington). The Minnesota case is 3M Co. v. Ivoclar Vivadent AG, 11-cv-3488, U.S. District Court, District of Minnesota (Minneapolis).

To see the patent, click: 5,936,006.

--Editors: Fred Strasser, Stephen Farr

To contact the reporter on this story: Phil Milford in Wilmington, Delaware, at pmilford@bloomberg.net

To contact the editor responsible for this story: Michael Hytha at mhytha@bloomberg.net.