Ohio Rev. Code § 1701.36: Shares deemed retired.

(A) Whenever convertible shares are converted into shares of another class, the shares surrendered upon such conversion shall be deemed retired and shall not be reissued as convertible shares.

(B) Whenever redeemable shares are redeemed, purchased, or otherwise acquired by the corporation, such shares shall be deemed retired.

(C) Shares released from subscription shall be deemed retired.

(D) Unless otherwise provided in the articles, the directors may retire treasury shares.