Oregon Revised Statutes Corporations and Partnerships § 60.317

(1) The articles of incorporation or the bylaws may provide for staggering the terms of directors by dividing the total number of directors into two or three groups, with each group to be as nearly equal in number as possible.

(2) If the terms of the directors are staggered, the terms of directors in the first group expire at the first annual shareholders' meeting after their election, the terms of the second group expire at the second annual shareholders' meeting after their election and the terms of the third group, if any, expire at the third annual shareholders' meeting after their election. At each annual shareholders' meeting held thereafter, directors shall be chosen for a term of two years or three years, as the case may be, to succeed those whose terms expire.

(3) If the corporation has cumulative voting, terms of directors may be staggered only if authorized by the articles of incorporation and each group of directors contains at least three members.