WASHINGTON, Nov 5 (Reuters) - The U.S. Supreme Court on Tuesday heard arguments in a case of warring legal doctrines raised by a heart pacemaker patent fight between giant medical devices company Medtronic Inc and privately owned Mirowski Family Ventures LLC.
The case stems from Medtronic's decision to request a declaratory judgment that some of its pacemakers do not infringe on technology patented by Mirowski and licensed to Boston Scientific and Guidant Corp, part of Boston Scientific and Abbott Laboratories.
Medtronic licensed the patents in question, but in 2007, Mirowski Family Ventures claimed Medtronic was developing new products that would justify royalty payments. Medtronic filed suit, seeking an adjudication that it did not need to pay.
A court in Delaware said Medtronic was not infringing on the patents, but the U.S. Court of Appeals for the Federal Circuit threw out that ruling.
Under legal doctrine, the company which files a lawsuit must prove its case. In this instance, that is Medtronic. And, under the same doctrine, a company which claims infringement must prove that infringement. In this case, that would be Mirowski.
The justices focused most of their energies on Mirowski's lawyer in an almost one-hour hearing focused on which side bears the burden of proof, but legal experts declined to guess which way the court might rule.
"We've said time and again that the burden of proof normally does not shift. What is different here?" Justice Antonin Scalia asked Arthur Neustadt, representing Mirowski Family Ventures.
In about five to 10 percent of patent infringement cases, many of them high stakes cases having to do with expensive medical devices, a company paying licensing fees will sue the patent holder, asking for a ruling that they don't infringe, in order to stop paying royalties, said Daniel Ravicher, director of the Public Patent Foundation, which seeks to prevent abuse of the patent system.
Two patents gave rise to the case. Both have to do with cardiac resynchronization therapy, a pacemaker which detects when the heart beats out of sync and then emits tiny shocks of electricity to correct its rhythm. It is used to treat congestive heart failure.
But the Supreme Court case is not about patent infringement. Instead, the court is attempting to decide which of the two legal doctrines should apply in an instance where a company sues another company to seek a declaratory judgment of non-infringement.
"There are other rules on burden of proof," Justice Ruth Bader Ginsburg said to Neustadt. "For example, the party who has better access to the information. So it's not as though there is this a firm rule with no exceptions."
The Supreme Court has a long history of disagreeing with the Federal Circuit, which specializes in patent appeals.
"The court asked many more questions of Arthur Neustadt and was far more friendly to Seth Waxman (for Medtronic) in the oral argument," said Jim Crowne, director of legal affairs for the American Intellectual Property Law Association.
A ruling is expected by the end of June.
The case is Medtronic v Boston Scientific Corp, Guidant Corp, and Mirowski Family Ventures, U.S. Supreme Court, No. 12-1128.