A federal appeals court Wednesday handed Microsoft Corp. yet another loss in its long-running battle to keep free-lancers and agency workers from participating in its lucrative employee stock purchase plan.

In doing so, the Ninth Circuit U.S. Court of Appeals also chastised a Seattle district court judge for essentially ignoring its earlier holdings in the case. The ruling Wednesday in Vizcaino v. Microsoft Corp., 99-35013, greatly expanded a class that Microsoft is liable to from about 500 workers to more than 5,000.