A Commonwealth Court panel has ruled that an employer defending against a workers’ compensation claim petition on the ground that the injury occurred at the claimant’s other job does not have to join the other employer in order to pursue its defense.

Judges Mary Hannah Leavitt and Renee Cohn Jubelirer — with Judge Doris A. Smith-Ribner concurring — reversed an adjudication of the Workers’ Compensation Appeal Board that said an employer couldn’t pursue the defense that another employer is liable for a claimant’s injuries without joining that employer as a defendant in the case.