§ 103. Nonenforceability of undertakings in conflict with public policy; “yellow dog” contracts

• (a) Either party to such contract or agreement undertakes or promises not to join, become, or remain a member of any labor organization or of any employer organization; or
• (b) Either party to such contract or agreement undertakes or promises that he will withdraw from an employment relation in the event that he joins, becomes, or remains a member of any labor organization or of any employer organization.