SAN FRANCISCO — A federal judge has sanctioned LifeScan Inc. for violating a protective order in a patent fight between companies in the blood glucose testing industry.

In an order issued Wednesday, U.S. District Judge William Orrick III of the Northern District of California ordered the Johnson & Johnson subsidiary to pay Shasta Technologies, Decision Diagnostics Corp., PharmaTech Solutions and Conductive Technologies a total of $41,914 in attorney fees. The companies moved for sanctions after LifeScan admitted it used confidential information to notify its rivals’ distributors of a preliminary injunction that had been issued against them.