Okla. Stat. tit. 43, § 43-20: Computation of time

A. Marriage licenses shall be issued to all applicants who are

entitled under the laws of the State of Oklahoma to apply for a

marriage license and contract matrimony. Once issued, the marriage

license shall be valid for thirty (30) days and the marriage

ceremony shall be performed no later than thirty (30) days from the

date the license is issued. The marriage license and completed

marriage certificate shall be returned to the court clerk for

recording no later than thirty (30) days from the date the license

was issued.

B. The time within which an act is to be done, as provided for

in Title 43 of the Oklahoma Statutes, shall be computed by excluding

the first day and including the last day. If the last day is a

legal holiday as defined by Section 82.1 of Title 25 of the Oklahoma

Statutes, it shall be excluded. The provisions of this section are

hereby declared to be a clarification of the law as it existed prior

to June 1, 2000, and shall not be considered or construed to be a

change of the law as it existed prior to June 1, 2000. Any action

or proceeding arising under Title 43 of the Oklahoma Statutes prior

to June 1, 2000, for which a determination of the period of time

prescribed by this section is in question or has been in question

due to the enactment of Section 2006 of Title 12 of the Oklahoma

Statutes shall be governed by the method for computation of time as

prescribed by this section.