Fridley-based Medtronic Inc. was slapped Monday with a $10 million fine and additional fees for the conduct of its defense in a federal patent infringement trial last year.

U.S. District Court Judge Edward Harrington imposed the fine and ordered Medtronic to pay a portion of the plaintiff's attorneys fees from the Massachusetts case over spinal screws that resulted in a $226.3 million judgment against Medtronic.

"The defendants prolonged the proceedings unnecessarily [thus unduly imposing upon the jury's time]," Harrington wrote in a five-page order.

Medtronic's legal team also "elected to proceed with a defense that threatened to mislead and confuse the jury," the judge said. "The defendants here clearly sought to take advantage of the technical and legal complexities inherent in this case."

Harrington said Medtronic's attorneys attempted to "obscure, evade or minimize" a previous federal court ruling on the patent in the case with their own expert witnesses.

Medtronic was represented by New York-based Dewey & LeBouef, an international law firm with 1,400 attorneys.

Medtronic said it will appeal Harrington's order on the grounds that "all trial issues were properly litigated by Medtronic's counsel," the company said in a statement.

The judge also said Medtronic's conduct entitled attorneys for the plaintiff, Johnson and Johnson's DePuy division, to recover 15 percent of certain attorneys fees from Medtronic. But the judge also ruled that portions of the case "were well and properly litigated" by the defense attorneys.

DePuy sued Medtronic in Boston claiming Medtronic's Vertex spinal screws infringed on the patent for its device used to treat spinal defects.

Medtronic's attempt to get the verdict overturned was denied in December by Harrington. The verdict is now being appealed by Medtronic.

"The case was vigorously defended by Medtronic's counsel on behalf of the company," Medtronic said in its statement.

David Phelps • 612-673-7269