Utah Code § 16-10a-810: Vacancy on board.

(1) Unless the articles of incorporation provide otherwise, if a vacancy occurs on a board of directors, including a vacancy resulting from an increase in the number of directors:

(a) the shareholders may fill the vacancy;

(b) the board of directors may fill the vacancy; or

(c) if the directors remaining in office constitute fewer than a quorum of the board, they may fill the vacancy by the affirmative vote of a majority of all the directors remaining in office.

(2) Unless otherwise provided in the articles of incorporation, if the vacant office was held or is to be held by a director elected by a voting group of shareholders:

(a) if one or more of the other directors elected by the same voting group are serving, only they are entitled to vote to fill the vacancy if it is filled by the directors; and

(b) only the holders of shares of that voting group are entitled to vote to fill the vacancy if it is filled by the shareholders.

(3) A vacancy that will occur at a specific later date, by reason of a resignation effective at a later date under Section 16-10a-807 or otherwise, may be filled before the vacancy occurs, but the new director may not take office until the vacancy occurs.