Okla. Stat. tit. 18, § 437.27

The provisions of the Oklahoma Uniform Securities Act of 2004, as amended, shall not apply to any note, bond or other evidence of indebtedness issued by any cooperative or foreign corporation transacting business in this state pursuant to this act, to the United States of America or any agency or instrumentality thereof, or to any mortgage or deed of trust executed to secure the same. The provisions of said Securities Act shall not apply to the issuance of membership certificates by any cooperative or any such foreign corporation.