(Adds details of litigation and proposed bond)
WASHINGTON, April 17 (Reuters) - Teva Pharmaceutical Industries Ltd on Thursday told the U.S. Supreme Court that it is willing to post up to a $500 million bond in return for a decision suspending a lower court ruling that would allow generic competitors to go on the market as soon as next month.
Teva already had asked the court for a stay of the July 2013 ruling by the U.S. Court of Appeals for the Federal Circuit that invalidated some of its patents for the top-selling multiple sclerosis drug Copaxone. The case was won by two teams developing generic versions of the drug: one comprising Novartis AG's Sandoz Inc and Momenta Pharmaceuticals Inc , and the other comprising Mylan Inc c and Natco Pharma Ltd.
The generic drugmakers suggested in their response to the stay application that Teva pay a bond, saying it would protect them should they eventually win the case and require compensation for the period in which they were prevented from entering the market.
The Supreme Court has yet to respond to Teva's stay application, submitted on April 7.
On March 31, the high court agreed to hear Teva's appeal of the appeals court ruling, but Teva subsequently filed additional court papers asking the high court to prevent the lower court ruling from going into effect while the case is decided.
The appeals court had declared several patents invalid, meaning patent protections were set to expire in May 2014 instead of September 2015. Teva made its last-ditch request for a stay because by the time the court has decided on the regular appeal, the generic drugs could already be on the market.
The Supreme Court will not be hearing oral arguments in the Teva case until its 2014 term begins in October. A ruling could come as late as June 2015.
The case is Teva v. Sandoz, U.S. Supreme Court, 13-854.
(Reporting by Lawrence Hurley; Editing by Howard Goller and Leslie Adler)