Okla. Stat. tit. 12A, § 12A-8-402

Assurance that Indorsement or Instruction is Effective.

(a) An issuer may require the following assurance that each

necessary indorsement or each instruction is genuine and authorized:

(1) in all cases, a guaranty of the signature of the

person making an indorsement or originating an

instruction including, in the case of an instruction,

reasonable assurance of identity;

(2) if the indorsement is made or the instruction is

originated by an agent, appropriate assurance of

actual authority to sign;

(3) if the indorsement is made or the instruction is

originated by a fiduciary pursuant to paragraph (4) or

(5) of subsection (a) of Section 8-107 of this title,

appropriate evidence of appointment or incumbency;

(4) if there is more than one fiduciary, reasonable

assurance that all who are required to sign have done

so; and

(5) if the indorsement is made or the instruction is

originated by a person not covered by another

provision of this subsection, assurance appropriate to

the case corresponding as nearly as may be to the

provisions of this subsection.

(b) An issuer may elect to require reasonable assurance beyond

that specified in this section.

(c) In this section:

(1) "Guaranty of the signature" means a guaranty signed by

or on behalf of a person reasonably believed by the

issuer to be responsible. An issuer may adopt

standards with respect to responsibility if they are

not manifestly unreasonable.

(2) "Appropriate evidence of appointment or incumbency"

means:

(i) in the case of a fiduciary appointed or qualified

by a court, a certificate issued by or under the

direction or supervision of the court or an

officer thereof and dated within sixty (60) days

before the date of presentation for transfer; or

(ii) in any other case, a copy of a document showing

the appointment or a certificate issued by or on

behalf of a person reasonably believed by an

issuer to be responsible or, in the absence of

that document or certificate, other evidence the

issuer reasonably considers appropriate.

Oklahoma Statutes - Title 12A. Uniform Commercial Code Page 446