Aramark Facility Services v. Service Employees International Union

After receiving SSA no-match letters for 48 employees (which the SSA issues for many reasons besides immigration violations), Aramark (defendant) gave employees three days to prove they'd applied for new social security cards and fired 33 who didn't comply; an arbitrator ordered reinstatement and back pay for lack of convincing evidence of undocumented status, but the district court voided the award as violating immigration public policy, finding the employees' failure to provide proof gave Aramark constructive knowledge of their status.