Okla. Stat. tit. 12, app 1 R. 1.156
Unless a different schedule is ordered by this Court, the Brief-in-chief of the appellant shall be filed with the Clerk of this Court within twenty (20) days after the filing of the Notice of Completion of Record. Appellee shall have twenty (20) days after the filing of appellant's brief within which to file an Answer Brief. Appellant may file a Reply Brief within ten (10) days after the filing of appellee's Answer Brief. If the appellant does not desire to file a Reply Brief, then appellant shall so notify all parties and the Clerk of this Court. The form and content of the briefs shall comply with Rules 1.10 and 1.11.
Copies of briefs shall be mailed to all other parties, the Commissioner and the Attorney General.
Okla. Stat. tit. 12, app 1 R. 1.156