Okla. Stat. tit. 70, § 70-5-181: Registration of certificates of indebtedness or bonds –

Recording of payment.

The treasurer of a school district to whom a certificate of

indebtedness or bond is directed for payment shall register the

certificate of indebtedness or bond by entering the number, the

date, the name of the payee, the fund upon which it is drawn and the

amount and shall write on the certificate or bond the date of

registration and the name of the treasurer. Certificates of

indebtedness or bonds shall be registered in the numerical order in

which they are issued and, after registration, shall be given to the

encumbrance clerk. No certificate of indebtedness or bond shall be

a valid charge until registration by the treasurer. A board of

education may contract for and pay a registrar or transfer agent to

transfer ownership or change of payee of any certificate of

indebtedness or bond issued by the school district and to maintain

relevant books and records. The treasurer shall record payment of

certificates of indebtedness or bonds and mark “paid” on the face of

paid certificates of indebtedness or bonds.