13 GCA § 8105: Securities Negotiable; Burden of Proof.

(1) Securities governed by this division are negotiable instruments.

(2) In any action on a security

(a) Unless specifically denied in the pleadings, each signature on the security or in a necessary indorsement is admitted;

(b) When the effectiveness of a signature is put in issue the burden of establishing it is on the party claiming under the signature but the signature is presumed to be genuine or authorized;

(c) When signatures are admitted or established production of the instrument entitles a holder to recover on it unless the defendant establishes a defense or a defect going to the validity of the security; and

(d) After it is shown that a defense or defect exists the plaintiff has the burden of establishing that he or some person under whom he claims is a person against whom the defense or defect is ineffective (Section 8202).