Same-sex marriages in Oklahoma became lawful following the U.S. Supreme Court’s decision not to act on a petition for review of a decision by the 10th Circuit Court of Appeals, which had upheld a district court decision striking down Oklahoma’s ban on same-sex marriage (Bishop v. Smith, 760 F.3d 1070 (10th Cir. 2014)).
Reciprocity. Same-sex and opposite-sex marriages legally performed in other jurisdictions are recognized as legal marriages in Oklahoma.
The U.S. Supreme Court issued a decision in June 2015 legalizing same-sex marriage in all states and requiring all states to recognize same-sex marriages legally performed in other jurisdictions (Obergefell v. Hodges, No. 14-556 (6/26/15)).