Article 19 of Municipality Law

A Municipal Council member may not combine his Municipal Council membership with membership of the board of directors of any company or holding any public office. If a member is in one of the situations of combination referred to in the preceding paragraph, he shall specify, within the eight days following the occurrence of the combination, which of the two he chooses. If he fails to do so, he shall be deemed to have chosen the more recent of them. Where the validity of membership is challenged, the combination shall not be deemed to exist until the date of issuance of the final decision rejecting the challenge.