ORS 662.030: Restrictions in employment contracts on affiliation with labor or employer organization unenforceable.

Any undertaking or promise described in this section or any other undertaking or promise in conflict with the public policy declared in ORS 662.020 is declared to be contrary to the public policy of Oregon and is not enforceable in any court of this state and does not afford any basis for the granting of legal or equitable relief by any such court, including specifically, every undertaking or promise made after June 6, 1931, whether written or oral, express or implied, constituting or contained in any contract or agreement of hiring or employment between any individual, firm, company, association or corporation, and any employee or prospective employee of the same, whereby:

      (1) 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.

      (2) Either party to such contract or agreement undertakes or promises that the party will withdraw from an employment relation in the event that the party joins, becomes or remains a member of any labor organization or of any employer organization.