This section is from the book "The Law Of Contracts", by William Herbert Page. Also available from Amazon: Commercial Contracts: A Practical Guide to Deals, Contracts, Agreements and Promises.
(1) A written instrument has no legal effect until execution, and therefore until it is executed its language may be changed at the pleasure of the party drafting it, subject, of course, to the qualification in case of contracts that the adversary party must assent to the instrument in its final form to give it validity. Alteration before delivery makes the contract as delivered the true contract as between the parties thereto, prior negotiations, including the contract as drafted, being merged by the delivery of the contract as ultimately agreed upon.1 On the same principle alteration of a deed with the consent of the parties and before delivery,2 or alteration after delivery if followed by redelivery,3 does not affect its validity. Putting revenue stamps on a shipping receipt is not in law an erasure of the provisions covered by such stamps, so as to prevent them from being a part of the contract.4 Alteration before final delivery discharges parties to the altered instrument who did not consent to such alteration, if the alteration affects their rights in any substantial way.5 If A is the maker of a note, B a payee and X a party to the note for the accommodation of A, a change made before final delivery by A, by the consent of A and B, but without X's consent, will discharge X.6 Indorsers of a note given by a corporation may set up an alteration made by the president of the corporation after indorsement but before delivery.7
1 Pelton v. Lumber Co., 113 Cal. 21; 45 Pae. 12; Bucki v. Seitz, 39 Fla. 55; 21 So. 576; Winkles v. Guenther, 98 Ga. 472; 25 S. E. 527 : Prather v. Zulauf, 38 Ind. 155.
2 Date of notary's certificate altered. Miller v. Williams, 27 Colo. 34; 59 Pac. 740.
3 Abbott v. Abbott, 189 HI. 488; 82 Am. St. Rep. 470; 59 N. E. 958.