Okla. Stat. tit. 59, § 59-46.26
Acceptance of compensation from other than client -
Unlawful.
It shall be unlawful for an architect to accept or receive
compensation, directly or indirectly, from another than his or her
client in connection with the reparation, alteration or construction
of a building or structure in relation to which he shall have
accepted employment in any manner.