
39 Mich. App. 40 (1972)
197 N.W.2d 129
BELT
v.
WOLPIN COMPANY
Docket No. 10056.
Michigan Court of Appeals.
Decided February 28, 1972.
*41 Shapero, Shapero & Cohn, for defendants.
Before: V.J. BRENNAN, P.J., and J.H. GILLIS and VAN VALKENBURG,[*] JJ.
Leave to appeal denied, 388 Mich 786.
PER CURIAM.
On October 13, 1966, plaintiff brought suit against defendants for breach of an alleged oral leasing agreement. Plaintiff averred that in September 1959, defendants ha` orally contracted to lease trucking equipment from plaintiff, and that defendants had agreed that the leasing contract was to be permanent in duration, or for at least a ten-year period. Defendants' answer argued that any prior oral agreement between the parties had been wholly merged and integrated into two written leasing contracts executed in October and December of 1959. The trial court granted partial summary judgment for defendants, concluding that any prior oral agreement had been wholly merged into the subsequent written leasing agreements, and such oral contract could not therefore serve as the basis for the law suit.
Plaintiff then added another count to his complaint, alleging defendants' breach of a written leasing agreement. Defendants contended that any liability they might have had to plaintiff was completely discharged by plaintiff's action in indorsing and cashing several checks received from defendants, which bore a condition that the payee by indorsing *42 or cashing them acknowledges full satisfaction of the obligation of the drawer. The trial judge again agreed with defendants' contention, and granted them partial summary judgment. Plaintiff appeals the decisions of the trial court and brings four allegations of error, only two of which merit our discussion.
Plaintiff first contends that the trial court erred in concluding that any prior oral leasing agreement between the parties had been wholly merged and integrated into subsequent written leasing agreements, and therefore could not support a legal action. An analysis of the written contracts between the parties reveals that they are clear, unequivocal, and unambiguous. Each contract contains a provision limiting its duration to a one-year period. It is difficult to avoid the conclusion that "[t]he written [agreements] before us in this appeal [appear] to have been designed to integrate the prior oral understandings of the parties". Siporin v Adler, 364 Mich 549, 553 (1961). In such a case all previous parol contracts relating to the same subject matter are regarded as merged in the written contract, and the latter is conclusively presumed to embrace all that was intended to be included and to be the best possible evidence of the intent and the meaning of the parties bound by it. Brachman v Wheelock Inc, 343 Mich 230 (1955). The trial court correctly so held.
Plaintiff secondly challenges the trial court's award of summary judgment for defendants pursuant to its conclusion that, as a matter of law, any liability which defendants might have had under a written leasing agreement had been released and discharged. The record shows that several checks which defendants mailed to plaintiff in response to the latter's rental invoices bore certain conditions at the time of mailing, but that additional modifying *43 clauses appeared on these checks when they were returned by defendants' bank after payment. The language on the final check, dated June 26, 1961, is typical and reads as follows:
"In full and final settlement, payment and discharge of any and all claims of every nature and description and whether accrued or contingent to date hereof including any claims under contract terminated May 15, 1961."
After this check had been indorsed and cashed by plaintiff, and was returned by defendants' bank, it contained the additional words "but, it is understood that this payment applies only to truck rental charges". An affidavit filed by plaintiff stated that he did not recall seeing the notations on the checks, and that he had no information or knowledge as to the origin of the additional modifying clauses. The trial judge concluded that defendants had satisfactorily established the fact that they had entered settlement provisions upon the checks, and that plaintiff had not succeeded in raising a factual issue on this point. The trial judge then decided that plaintiff's indorsement and cashing of these checks, bearing the condition therein stated, effectively released defendants from all liability for breach of contract, either under the doctrine of accord and satisfaction, or alternatively, under the theory that the indorsed checks constituted a signed writing discharging defendants' obligations pursuant to MCLA 566.1; MSA 26.978(1).
Our examination of the evidence confirms the correctness of the trial court's decision. The provision appearing on the check of June 26, 1961 clearly discharged any claim plaintiff might have had for breach of a written leasing agreement. We hold that this check, when indorsed and cashed by plaintiff, constituted a signed writing which effectively *44 discharged defendants' obligations, pursuant to the above cited statute. See Thal v Detroit Board of Education, 316 Mich 351 (1946). It is, of course, well known that the subsequent addition by second parties of purported modifying clauses could not alter the legal effect of the settlement provision originally placed upon the checks by defendants. Deuches v Grand Rapids Brass Co, 240 Mich 266 (1927). Having concluded that there was a legally sufficient discharge of defendants' obligations, we need not decide whether accord and satisfaction occurred in the instant case.
Affirmed. Costs to appellees.
NOTES
[*]  Former circuit judge, sitting on the Court of Appeals by assignment pursuant to Const 1963, art 6, § 23 as amended in 1968.
