N.Y. Uniform Commercial Code Law § 2-208: Course of Performance or Practical Construction

Section 2--208. Course of Performance or Practical Construction.

(1) Where the contract for sale involves repeated occasions for

performance by either party with knowledge of the nature of the

performance and opportunity for objection to it by the other, any course

of performance accepted or acquiesced in without objection shall be

relevant to determine the meaning of the agreement.

(2) The express terms of the agreement and any such course of

performance, as well as any course of dealing and usage of trade, shall

be construed whenever reasonable as consistent with each other; but when

such construction is unreasonable, express terms shall control course of

performance and course of performance shall control both course of

dealing and usage of trade (Section 1--205).

(3) Subject to the provisions of the next section on modification and

waiver, such course of performance shall be relevant to show a waiver or

modification of any term inconsistent with such course of performance.