On 5/21/18, US Supreme Court held that it's legal for employers to prohibit workers from joining together to sue the company over discrimination, wage theft, and other workplace violations. Now workers who sign arbitration clauses with class-action waivers can only file claims individually through private arbitration.
Collective Bargaining: Negotiation and Contracts by 
Labor and Employment Arbitration by 
Labor Arbitration Reports by 
Ohio Civil Service & Collective Bargaining: Laws and Rules Annotated by