Okla. Stat. tit. 58, § 58-339: Suit on rejected claim

When a claim is rejected, either by the executor or

administrator, or the judge of the district court, the holder may

bring suit as an ancillary proceeding in the probate case or as an

independent action, according to its amount, against the executor or

administrator. Any proceeding or action shall be filed within

forty-five (45) days after the date the claim was rejected, if it be

then due, or within two (2) months after it becomes due; otherwise

the claim is forever barred. If suit be brought as an ancillary

proceeding, no process need be issued for service on the executor or

administrator and pleadings and practice therein shall be the same

as if an independent action had been brought to recover upon the

claim.