Opinion
REYNOSO, J.
Eileen Baldwin appeals from a judgment awarding respondents—Jessup Farms, a general partnership, and its partners, individual [643]*643members of the Jessup family—contribution for payments made on an obligation for which appellant was a co-obligor; ordering specific performance in favor of respondents of a contract for the purchase of securities in Holstein Heifer Ranch, Inc. (HHR); and denying appellant’s cross-complaint for an equitable lien on stock transferred to respondents.
The primary issue we consider is whether payments made by HHR, in which appellant and respondents owned stock, were properly apportioned by the trial court among four outstanding obligations. We examine Civil Code section 1479, subdivision Three, which provides in pertinent part that unspecified payments be first applied to the obligation with the earliest maturity date. Particularly, we inquire whether a subsequent instrument can renew the maturity date of an earlier note so that both obligations can be said to mature simultaneously. This case thus presents a narrow question of statutory construction. A subsidiary issue involving respondents’ purchase of stock from appellant’s husband requires us to examine the record to determine if substantial evidence supports the trial court judgment that respondents were bona fide purchasers without notice of an alleged unperfected security interest in favor of appellant.
In 1972 HHR had executed a promissory note for which it was principal obligor. Appellant and respondents signed the note as co-obligors. Three subsequent notes executed by HHR were signed by respondents but not appellant. Prior to 1975, HHR made payments in excess of the amount due on the 1972 note but did not specify to which of the outstanding obligations the payments should be applied. After 1975 respondents made additional payments for which they sought contribution from appellant. Further, in 1973 appellant had executed a property settlement agreement which assigned to her husband her interest in HHR stock subject to a purported lien in her favor. Later, in 1974, respondents acquired this stock from appellant’s husband pursuant to an option contract.
Appellant makes two contentions on appeal: (1) HHR’s payments should have been first applied to the 1972 note thereby extinguishing that obligation prior to the time respondents made the payments for which the trial court awarded contribution, and (2) she has an equitable lien on the HHR stock transferred by her husband to respondents.
For the reasons discussed below, we conclude that the 1972 note had the earliest maturity date irrespective of subsequent renewal instruments and that, therefore, HHR’s unspecified payments should have been first applied to extinguish this obligation. Accordingly, we reverse that part of the trial court judgment ordering appellant to make contribution to respondents. With respect to appellant’s second contention, we conclude that substantial evidence supports the trial court’s ruling that respondents were bona fide purchasers of the [644]*644Baldwin stock; we therefore affirm that part of the judgment ordering specific performance of the option contract and dismissing appellant’s cross-complaint for an equitable lien.
I
Summary of Facts
Appellant’s two contentions make necessary a detailed discussion of somewhat complex facts. The principal evidentiary matters relevant to this appeal, however, were substantially undisputed as the parties stipulated to the various transactions by which Jessup Farms obtained ownership of all the stock in HHR and made payments on debts incurred in its operation. We summarize the events and transactions central to this appeal.
In early 1970 appellant and her then husband, codefendant Wayne Baldwin,1 both residents of Idaho, owned 100 percent of the stock in HHR, an Idaho corporation. On February 16, 1970, Jessup Farms of Glendale, California, purchased 200 shares of HHR stock directly from the corporation. Concurrently with this stock transaction, the parties entered into a separate, written stock purchase agreement whereby the Baldwins agreed to sell and Jessup Farms agreed to buy an additional 150 shares of HHR stock for $105,000.2 The 350 shares so acquired by Jessup Farms represented 50 percent of the stock of HHR, with the Baldwins then owning the remaining 50 percent as husband and wife.
Since 1969 HHR had been incurring a substantial indebtedness to FresnoMadera Production Credit Association (PCA), an agricultural lender, in connection with the purchase, care and feeding of HHR livestock. On May 19, 1972, HHR executed in favor of PCA a promissory note in the amount of $5,135,571. This note (entitled “Renewal Promissory Note”) constituted a [645]*645renewal of certain existing indebtedness to PCA plus a commitment by PCA to make additional advances in the sum of $2,485,029.67. The 1972 note was executed by HER and by appellant and Mr. Baldwin in their individual capacities. PCA also demanded that the Jessups3 sign the note in light of their status as sole partners of Jessup Farms which, as noted, at the time owned 50 percent of EER. The partnership itself, however, was not named as a primary obligor on the note. The documents provide and the trial court found4 that the Baldwins and Jessups were individually liable as co-obligors with EER on the 1972 note. The documents specifically provide that the note was due on demand or, if no demand was made, on May 6, 1973. There being no demand by PCA, as of the due date on the note a balance of $3,218,804 remained unpaid.
At about this time, appellant and her husband separated and divorce proceedings were initiated. On June 15, 1973, one month after the 1972 note became due, the Baldwins executed a property settlement agreement whereby Mr. Baldwin assigned to appellant his interest in the 1971 stock purchase agreement with Jessup Farms. (See fn. 2, ante.) Concomitantly, appellant agreed to convey to her husband her interest in the remaining 50 percent of EER stock, held by the Baldwins as community property (the Baldwin stock), in exchange for the sum of $267,000 to be paid by Mr. Baldwin over a period of years. It was further agreed that the 350 shares of Baldwin stock transferred to Mr. Baldwin as his separate property were subject to a lien in favor of appellant to secure payment of the $267,000 obligation, and that Mr. Baldwin would place the stock in escrow to secure his performance of the property settlement agreement. This property settlement agreement was incorporated into the final decree of divorce executed in Idaho on March 18, 1974. Appellant stipulated at trial, however, that her ex-husband never performed his obligation to pledge the Baldwin stock and place it in escrow, and that her alleged security interest in the stock was never otherwise perfected pursuant to the method sanctioned by the Idaho Uniform Commercial Code. Instead, a certificate representing the Baldwin stock was executed in blank and left in the possession of appellant’s attorney.
On June 22, 1973, one week after execution of the property settlement agreement transferring appellant’s interest in the Baldwin stock to her husband, EER executed in favor of PCA a second renewal promissory note in the amount of [646]*646$6,282,838. This note incorporated the unpaid principal plus interest on the 1972 note ($3,268,753.26) as well as new advances. The 1973 note, in addition to evidencing the obligation created by the new advances, expressly provides that it is given not in satisfaction of, but only for the purpose of renewing the unpaid balance on the 1972 note. This second note, by its terms, matured on May 6, 1974, if no prior demand was made; it also specifically states on its face that the maturity date of the first note was May 6, 1973. The 1973 note was thus executed one month and sixteen days after the 1972 note had matured.
The 1973 note was executed by HER, the Jessups, and Mr. Baldwin. Appellant, however, did not execute the 1973 note in her individual capacity although she did sign it in her capacity as treasurer of EER. This is consistent with the parties’ stipulation at trial that the Jessups and Baldwins had entered into an oral apportionment agreement whereby they agreed that any personal liability arising from the PCA indebtedness would be apportioned in accordance with their respective stock ownership in EBR. Thus, appellant understandably refused to sign the 1973 note as an obligor as she no longer owned stock in EBR (having conveyed her interest in the remaining 50 percent of EER stock to Mr. Baldwin pursuant to the property settlement agreement). It will be recalled, however, that at the time the 1972 note was executed (by the Jessups and both Baldwins), Jessup Farms owned 50 percent of the EER stock and the Baldwins owned the remaining 50 percent. The execution of the 1972 note is thus also consistent with the stipulated apportionment agreement.
On January 10, 1974, EER executed a third note, payable on demand, in favor of PCA in the amount of $42,000. This note was executed by the Jessups, but was not signed by appellant or her ex-husband Wayne Baldwin. The record does not disclose why Mr. Baldwin was not required to sign the third note.
Subsequent to the execution of the 1973 note, and continuing until after execution of the third note, EER had made numerous payments to PCA. As earlier noted, at the time the 1973 note was executed an unpaid balance of $3,268,753.26 was still due on the 1972 note. As a result of EER’s continuing and substantial payments, EBR was able to pay PCA a sum in excess of the unpaid balance of the 1972 note, the only note signed by appellant as an obligor. PCA, however, applied EER’s payments to the total indebtedness and made no specific allocation to any of the outstanding obligations. PCA kept a running account which showed only the total due, and EER had not designated in what manner the payments should be applied with respect to the outstanding promissory notes. Despite the large payments by EER, a substantial amount remained of BER’s total indebtedness to PCA.
Therefore, on March 13, 1974, PCA made written demand on EER, the Jessups, and the Baldwins for payment on the balance due on the total in[647]*647debtedness. PCA’s demand letter made specific suggestions to HER on how to liquidate its assets in order to pay its indebtedness to PCA. The Baldwins paid nothing in response to the demand letter. Although EER began an orderly liquidation of its assets, it too was unable to comply with the demand.
Thereafter, Jessup Farms devised a plan to buy out Wayne Baldwin’s interest in EER. Accordingly, on March 19, 1974 (the day following entry of the final decree of divorce), Mr. Baldwin and respondents, each represented by counsel, executed a written agreement granting Baldwin a 60-day option to acquire Jessup Farms’ interest in the EER stock if he paid all of BER’s debts. The March 19 option agreement further provided that Wayne Baldwin’s failure to exercise the option would entitled respondents to the Baldwin stock. An escrow account was opened with PCA. Appellant’s attorney deposited the certificates representing the Baldwin stock in the PCA escrow to facilitate consummation of the March 19 agreement. Subsequently, Wayne Baldwin failed to exercise the option agreement thereby entitling Jessup Farms to the remaining 50 percent of the EER stock without having to pay anything for it. Mr. Baldwin, however, refused respondents’ request to deliver the stock certificates. At the time of trial the Baldwin stock remained in possession of PCA.
On May 8, 1974, EER executed a fourth promissory note in favor of PCA for $336,474. This final note was signed by all the partners of Jessup Farms, except Roger Jessup, but neither of the Baldwins signed the note.
On December 30, 1974, PCA wrote a second demand letter demanding payment of the total indebtedness of EER. The Baldwins again ignored PCA’s demand. Respondents, however, decided to protect their interest in EER and, on January 3, 1975, they made the first of three payments totaling $1.1 million.5 These payments were apparently motivated by respondents’ concern that their personal assets, including their interests in the partnership, would be vulnerable to loss. These latter payments, combined with EER’s earlier payments, were sufficient to extinguish the first two notes. PCA acknowledged at trial that the 1972 and 1973 notes were paid in full, and it affirmatively released and discharged all signatories from further liability.
After making these payments, respondents made written demands on each of the Baldwins for contribution. Respondents purported to seek contribution from appellant only insofar as she had agreed to be bound by the apportionment agreement which, as noted, provided that liability on the notes be apportioned according to the parties’ respective ownership interest in EER stock. Respondents were unable to obtain contribution from either of the Baldwins nor were they able to enforce the March 19 agreement with Mr. Baldwin.
[648]*648
Proceedings Below
On February 4, 1977, respondents filed an amended complaint seeking in three causes of action (1) a declaration that they owed nothing to appellant on the stock purchase agreement of 1971 because that balance was offset by her duty of contribution to respondents for the payments made after January 1975, and that Jessup Farms as full owner of the shares is entitled to possession; (2) a money judgment in the amount by which respondents’ contribution claim exceeded the amount owed to appellant under the stock purchase agreement of 1971; and (3) specific performance by Mr. Baldwin of the March 19 option agreement, and a declaration that Jessup Farms is legal owner of all HHR stock described in that agreement and entitled to possession of the certificates held by PCA representing those shares.
Appellant’s answer denied liability and alleged that as a surety, rather than a principal obligor, she was released from liability by respondents’ execution of the 1973 note which assertedly altered the 1972 note; that as assignee of Mr. Baldwin she was entitled to the proceeds of the stock purchase agreement of 1971; and that her liability terminated when she ceased to be a shareholder in HHR on June 15, 1973, the date the property settlement agreement was executed. Appellant by cross-complaint sought to recover from respondents the balance due on the stock purchase agreement of 1971, assigned to her by Mr. Baldwin, and to obtain a determination that respondents’ claim to the Baldwin stock under the March 19 option agreement is subject and subordinate to the lien in her favor under the property settlement agreement.
After a court trial, the court held that Civil Code section 1479, subdivision Three, controlled with respect to allocation of the amounts paid to PCA on the promissory notes; that appellant was a principal obligor on the 1972 note (see fn. 4, ante)-, and that the 1972, 1973 and both 1974 notes were all of the same “class” within the meaning of section 1479.6 Accordingly, the court applied all [649]*649payments made on the four notes by respondents and HHR ratably against the various liabilities. The court further ordered appellant to contribute to respondents one-half of the amount of respondents’ payments allocable to the 1972 note, less the amount respondents owed her under the stock purchase agreement of 1971, for a total of $127,838.82. (See Civ. Code, § 1432.) The court also ruled that Jessup Farms was entitled to immediate delivery and possession of the 105 shares of HHR stock which had remained in escrow under the terms of the stock purchase agreement of 1971.
Finally, the court dismissed appellant’s cross-complaint with prejudice. It found that Jessup Farms was a bona fide purchaser for value of the Baldwin stock held in escrow by PCA, and that consequently it was entitled to specific performance by Mr. Baldwin of the March 19 option agreement. The court thus found that Jessup Farms purchased the Baldwin stock without notice of appellant’s unperfected security interest in the stock created by the property settlement agreement. Concluding that appellant held neither a legal nor an equitable lien on the stock, the court ordered PCA to immediately deliver to Jessup Farms the Baldwin stock, representing the remaining 350 shares of HHR stock. As a result, respondents acquired ownership and possession of 100 percent of all issued and outstanding HHR stock.
II
Appellant’s contention that she is not liable in contribution
On appeal, appellant renews her claim—rejected by the trial court— that because payments in excess of the amount due on the 1972 note were made prior to the time respondents made the payments for which they were awarded contribution, she is not obligated to make any contribution. Thus, appellant argues, the payments made by HHR prior to January 1975 should have been first applied to extinguish the 1972 note, the only obligation for which she was a co-obligor, so that she should not have been held liable in contribution for payments made by respondent Jessup Farms on and after January 3, 1975. In support of this contention appellant makes a two-fold argument: that the four promissory notes were not of the same “class” within the meaning of Civil Code section 1479, and that this section purportedly requires that all payments be first applied to the “oldest debt,” here the 1972 note. We will conclude that the trial court erred in allocating the HHR and Jessup Farms payments ratably among the several obligations comprising the PCA indebtedness and in order[650]*650ing appellant to make contribution to respondents, but not for the reasons set forth by appellant.
Both parties assert that section 1479 controls this case.7 For present purposes the relevant portion of section 1479 is subdivision Three which provides for the allocation of unspecified payments applicable to any one of several obligations. Subdivision Three provides that where several obligations are owed and neither the debtor nor the creditor makes express application of a payment to a particular obligation within the time prescribed, the payment “must be applied to the extinction of obligations in the following order; and, if there be more than one obligation of a particular class, to the extinction of all in that class ratably:
[651]*651“1. Of the interest due at the time of performance.
“2. Of principal due at that time.
“3. Of the obligation earliest in date of maturity.
“4. Of an obligation not secured by a lien or collateral undertaking.
“5. Of an obligation secured by a lien or collateral undertaking.” (Italics added; see fn. 6, ante, for full text of statute.)
Because each of the obligations at issue embodies both principal plus accrued interest and because there is no question regarding the application of payments as between principal and interest, subsections 1 and 2 are not here relevant. We therefore consider, first, whether the trial court properly held that the subject promissory notes are of the same “class” so that the unspecified payments must be apportioned ratably among all the obligations;8 and, second, whether the 1972 note can be considered the “obligation earliest in maturity” under subsection 3 in light of the 1973 “renewal” note.
Appellant argues that the four promissory notes were not of the same class because each was executed at a different time and for a different amount and because, although HHR was the principal obligor on all the notes, each was executed by a different set of co-obligors. We are unpersuaded by this contention. Nothing in the statute supports appellant’s suggestion that several obligations are only of the same class if executed on the same date and for the same amount. Moreover, although subsections 4 and 5 establish separate categories for secured and unsecured obligations, these subsections draw no distinction based upon the type of security or the number of obligors who may be bound on the instrument.
Appellant relies heavily on Bank of America etc. Assn. v. Kelsey (1935) 6 Cal.App.2d 346 [44 P.2d 617], in support of her contention that the subject notes are obligations of different classes. That case, however, is not only inapposite, but it refutes appellant’s contention in dictum. The court in Kelsey simply held that a renewal note neither changed the underlying character of an obligation nor discharged the separate debts which it evidenced. (Id., at p. 353.) Although appellant emphasizes that the underlying obligation in that case involved four promissory notes each for different amounts and with dif[652]*652ferent execution dates, the court did not rely on these incidental differences. Rather, it concluded that the notes evidenced “two classes of obligations as defined by section 1479, . . .’’—those secured vis-a-vis those unsecured. (At p. 352.) The court then allocated payments first to the unsecured debt, with the surplus being applied to the secured debt. Thus, the distinction which led the court in Kelsey to find two distinct classes of obligations is totally absent here as the subject notes are all secured. Further, the Kelsey court stated in passing that “[there being no item of interest involved at the time of this payment, we are led to the second class mentioned in subdivision Three of section 1479, which embraces ‘principal due at that time’. ...” (At p. 353; italics added.)
Thus, Kelsey clearly stands for the proposition—though it does not specifically so hold—that the “classes” referred to in subdivision Three are the five categories there listed. We are persuaded by the Kelsey dictum that subdivision Three, read as a whole, establishes by its terms that subsections 1 to 5 constitute the “classes” of obligations to be given priority for purposes of allocating unspecified payments. We conclude that the most reasonable construction of the statute compels this interpretation and, accordingly, hold that the five categories specified in subsections 1 to 5 constitute the particular classes of obligations referred to in the first paragraph of subdivision Three.9 We therefore reject appellant’s contention that the factual circumstances surrounding the execution of the notes are dispositive in determining the “class” of the obligation.
Having so construed the term “class” as used in section 1479, we next turn to respondent’s contention that the trial court’s allocation of payments ratably among the four notes must be upheld either because all the notes share a “mutual classification as secured obligations,” thus making them of the same class pursuant to subdivision Three 5, or because all the notes matured on the same date thereby making them of the same class under subdivision Three 3.
No case supports the view that pro rata allocation is compelled if the notes are all secured under subsection 5. To so hold would lead to anomalous results. Because all obligations are either secured or unsecured, under respondents’ analysis subsections 1 to 3 would be rendered meaningless. Accepting this statutory construction would require only an initial determination of whether the obligations are secured or not; thereafter payments will always be apportioned ratably in contravention of the statutorily mandated priorities. Even where the several obligations include both secured and unsecured debts, only the unsecured debts will be given preference irrespective of the first three listed statutory priorities—interest, principal, and maturity date. Clearly, these [653]*653anomalous results indicate that this interpretation of section 1479 violates a fundamental principle of statutory construction: “. . . that legislation should be construed so as to harmonize its various elements without doing violence to its language or spirit.” (Wells v. Marina City Properties, Inc. (1981) 29 Cal.3d 781, 788 [176 Cal.Rptr. 104, 632 P.2d 217].)
As early as 1895, one court recognized the total unacceptability of such a statutory construction. In The Katie O’Neil (N.D.Cal. 1894) 65 Fed. 111, 117, the district court had occasion to interpret section 147910 and held that subsection 3 (date of maturity) must govern in a case where the obligations are either secured or unsecured, and that subsections 4 and 5 govern in cases where the comparison is between secured and unsecured obligations. With Katie O’Neil as a point of departure, we adopt a statutory construction that will best give effect to all the provisions of section 1479. (See Pacific Legal Foundation v. Unemployment Ins. Appeals Bd. (1981) 29 Cal.3d 101, 114 [172 Cal.Rptr. 194, 624 P.2d 244] [statutory interpretations which produce internal harmony and accord significance to each word and phrase are preferred].)
It is readily apparent that subsections 4 and 5 seek to effectuate the oft-cited proposition that courts will first apply unspecified payments to the discharge of the most precariously secured obligations. (See, e.g., Murdock v. Clarke (1891) 88 Cal. 384 [26 P. 601]; Walter Broderick & Associates, Inc. v. Monte Vista Lodge (1967) 253 Cal.App.2d 242 [61 Cal.Rptr. 679]; Eisendrath v. Bank of America (1953) 118 Cal.App.2d 434 [258 P.2d 13]; Bank of America etc. Assn. v. Kelsey, supra, 6 Cal.App.2d 346.) This policy favoring unsecured obligations over secured ones should not, however, be implemented so as to defeat the statutorily expressed policy of giving priority in the application of unspecified sums first to interest, then to principal and, finally, to notes with the earliest maturity date. Section 1479 expressly provides that these first three classes of obligations take precedence over the more general categories for unsecured and secured debts.11
That statute itself, if construed to effectuate its terms, therefore does not support the view that all secured obligations require pro rata application of payments simply by virtue of being secured. Rejecting a construction that would render the statute meaningless, we therefore conclude that subdivision Three’s pro rata provisions for “more than one obligation of a particular class” apply where there is more than one obligation within a particular subsection, [654]*654provided that such a “class” retains its payment priority as enumerated in the statutory scheme; i.e., subsections 1 through 5 in descending order of priority. Thus, where the notes at issue have different maturity dates, section 1479 requires that payments be applied to the notes with the earlier maturity date, in order, irrespective of whether secured or unsecured. Where, however, two or more obligations have the same maturity date, section 1479 mandates a ratable allocation among them (assuming all such obligations are either secured or unsecured).12
Applying this construction to the present case, respondents can nevertheless prevail if they can establish that the promissory notes had simultaneous maturity dates so that, under subsection 3, the obligations are a “class” subject to ratable allocation.13 (See Star Mill and Lumber Co. v. Porter (1906) 4 Cal.App. 470 [88 P. 497] [pro rata allocation of payments among mechanic lien claims maturing on the same date].)
Although conceding that the 1972 note states on its face that it is due, if no demand be made, on May 6, 1973, respondents nonetheless argue (1) that execution of the 1973 note “renewed” the due date of the first note, and (2) that the 1973 note, in turn, became due prior to its May 6, 1974, due date because of PCA’s first written demand. Because PCA demanded payment of the entire debt, respondents assert that the first three notes were thus due simultaneously on March 13, 1974, the date of PCA’s first demand. Respondents concede, however, that the fourth note, executed after the first demand, did not become due until PCA made its second written demand on December 30, 1974. In sum, respondents argue that payments should have been allocated among the first three notes since these, they allege, had the same maturity date.14
[655]*655Appellant, on the other hand, contends that payments should have been first applied to the earliest item of debt—the 1972 note. Appellant relies on misleading statements in two cases which suggest that payments must be first applied to the extinguishment of “the earliest item of debt” (Hollywood etc. Co. v. John Baskin, Inc. (1953) 121 Cal.App.2d 415, 430 [263 P.2d 665]) or “the oldest debt” (Los Angeles T. & S. Bk. v. Forve (1919) 45 Cal.App. 298, 300 [187 P. 438]). (Compare Star Mill and Lumber Co. v. Porter, supra, 4 Cal.App. at pp. 473-474 [“. . . the rule given in (section 1479) is not that the payment is to be applied to the obligation earliest in date, but to ‘the obligation earliest in date of maturity.’ ”].) Suffice it to state that section 1479 on its face repudiates appellant’s erroneous contention that the statute compels application of payments to the oldest debt first: subdivision Three 3 speaks of the maturity date of the obligations and not of the order in which the obligations were incurred. The statements in Hollywood Wholesale and Los Angeles Trust either appear to contemplate obligations of earliest maturity or are mere dicta; to the extent that those cases suggest a contrary rule, they are disapproved. Accordingly, consistent with the provisions of section 1479, we reiterate the settled rule that payments should be first applied to the obligation earliest in maturity, though not necessarily the oldest obligation. (Smith v. Renz (1954) 122 Cal.App.2d 535, 538 [265 P.2d 160]; Bradner v. Woods (1939) 30 Cal.App.2d 678, 681 [87 P.2d 69]; Ross v. McDougal (1936) 12 Cal.App.2d 172, 175 [55 P.2d 574].)
We now turn to respondents’ contention that the “nominal maturity date” of the 1972 note was renewed by virtue of the renewal provisions of the 1973 note. Relying on California Uniform Commercial Code section 3802, subdivision (l)(b),15 respondents assert that the 1973 note, as a matter of law, renewed the maturity date of the underlying obligation—the 1972 note—until such time as the renewal note itself matured. They argue that because the two notes must be deemed to have matured simultaneously, the trial court properly declined to allocate payments to the extinguishment of the 1972 note, and thus correctly found that appellant was liable in contribution.
Respondents’ contention with respect to the effect of section 3802 on the present transactions raises an issue which no California case has previously addressed, i.e., whether a new instrument renews the maturity date of an underlying obligation. The only case to date that discusses section 3802 at all does so in a context not here relevant.16 As will appear, we conclude that although there is no decisional authority directly on point, our reading of the statute precludes reaching the result sought by respondents—that section 3802 mandates that the maturity date of the underlying obligation be renewed as a matter of law.
[656]*656Section 3802 provides in pertinent part:
“(1) Unless otherwise agreed where an instrument is taken for an underlying obligation
“(b). . . the obligation is suspended pro tanto until the instrument is due or if it is payable on demand until its presentment. If the instrument is dishonored action may be maintained on either the instrument or the obligation',. . . .” (Italics added.)17
Paragraph 3 of the official comment to Uniform Commercial Code section 3-802 (which is identical to our § 3802) reads: “It is commonly said that a check or other negotiable instrument is ‘conditional payment. ’ By this it is normally meant that taking the instrument is a surrender of the right to sue on the obligation until the instrument is due, but if the instrument is not paid on due presentment the right to sue on the obligation is ‘revived.’ Subsection (l)(b) states this result in terms of suspension of the obligation. ...” (23 West’s Com. Code (1973 ed.) p. 503, Deering’s Ann. Cal. U. Com. Code (1970 ed.) p. 391; see also 10 Cal.Jur.3d (1974) Bills and Notes, § 104, pp. 117-118.)
At the outset we observe that section 3802 is applicable only when the parties do not otherwise agree.18 Here we are presented with an express contrary provision—the 1973 note states on its face that the parties agree that “ [t]his note is executed, . . . not in payment of, but for the purpose of renewing the unpaid balances” on the 1972 note, which is specifically identified as having a maturity date of May 6, 1973. Because the operation of section 3802 is expressly conditioned on there being no agreement to the contrary, we may then properly conclude that upon execution of the new instrument the parties unequivocally expressed an intent not to renew the maturity date of the underlying obligation. Moreover, the 1972 note, by its terms, had already matured more than a month prior to the execution of the 1973 note. In fact, PCA could have brought suit on the 1972 note as of May 6,1973. It is settled that an obligation “matures” when the holder of the note has a legal right to bring an action to force payment. (Bur-[657]*657rill v. Robert Marsh & Co., Inc. (1934) 138 Cal.App. 101, 106 [31 P.2d 823].) Thus, it does not appear that section 3802 is applicable, but even if it is, that section cannot, as we shall explain, serve to “unmature” a note that had already matured.
We recognize of course that the parties in signing the 1973 note obviously intended an extension of time in which to pay the original indebtedness evidenced by the 1972 note. The question then is whether, pursuant to section 3802, the renewal note not only suspends the underlying monetary obligation but also affects the terms of the underlying note—specifically, the maturity date thereof. We have discovered one out-of-state decision which has held, albeit in a factually dissimilar context, that under the Delaware counterpart of Uniform Commercial Code section 3-802 (5A Del. Code, § 3-802) a dishonored instrument does not change the due date of the underlying obligation. (See Moore v. Travelers Indem. Ins. Co. (Del.Super. 1979) 408 A.2d 298, 301.) Furthermore, Bank of America etc. Assn. v. Kelsey, supra, 6 Cal.App.3d 346, which, as earlier noted, held that a renewal note neither changes the underlying character of the obligation nor discharges the debts which it evidences, is helpful in this regard. In Kelsey, the bank held an unsecured $4,000 note and secured notes totalling $7,000. After a $1,600 payment was made, the remaining $9,400 debt was consolidated into a single note which, as in the present case, was designated a renewal note not taken in payment of the prior notes. The Court of Appeal held that under Civil Code section 1479 a second payment of $5,000 must be first applied to the unsecured portion of the total $9,400 debt—the $2,400 still owing on the $4,000 unsecured note. It is clear, therefore, that for purposes of subdivision Three of section 1479 we look to the original character of the underlying note irrespective of the execution of a subsequent renewal note. In our case we are concerned with the maturity date of the underlying note. The undisputed facts are that the 1972 note had already matured by the time the 1973 note was executed. Because under Kelsey the original character of the 1972 note is preserved, a fortiori the 1973 note cannot “unmature” it for purposes of Civil Code section 1479. (See also Easton v. Ash (1941) 18 Cal.2d 530, 538 [116 P.2d 433] [provisions of renewal note “cannot operate to bind (previous) instruments into a single inseparable transaction.”].)
Moreover, applying section 3802 to the facts of this case, it is apparent that because the statute provides only that the underlying obligation is “suspended pro tanto”19 until the new instrument is due or, if it is payable on demand, until [658]*658its presentment (see 3 Anderson, On the Uniform Commercial Code (2d ed. 1971) § 3-802:4, p. 141), it follows that the terms of the underlying obligation (here maturity date) are also merely suspended until the new instrument is due. Thus, in spite of the execution of the 1973 note, appellant’s obligation to PCA continued to be measured by the terms of the 1972 note, the only instrument she signed as a co-obligor.20 Because section 3802 provides that the mere fact that a lender executes a subsequent renewal instrument does not constitute an ex-tinguishment of the original indebtedness, the 1972 obligation (including its terms) remained a viable instrument which continued to be held by PCA. It is' therefore clear that the parties who executed the 1973 note did not intend to discharge the original indebtedness since the note is expressly entitled “Renewal Promissory Note,” and it specifically incorporates the balance due on the 1972 note. Accordingly, appellant’s obligation remained the same under the 1973 note; “it is in substance and in fact the same indebtedness evidenced by a new promise.” (Bank of Austin v. Barnett (Tex.Civ.App. 1977) 549 S.W.2d 428, 430.)
In the present case, payment was due with respect to the 1972 note, by its terms, on May 6, 1973, since no prior demand for payment was made. Assuming that pursuant to section 3802 the maturity date of the first note was suspended by execution of the 1973 note, this latter note was “dishonored” as it also was not paid upon demand. At the time payment was not presented upon demand, the underlying obligation was “revived,” thus providing PCA—the holder of both notes—with the option to sue either on the new instrument or on the first note.21 Consequently, the original maturity date of the 1972 note remained unaltered either (1) pursuant to case law as a result of the fact that an action was maintainable by PCA upon HHR’s failure to comply with the demand (Burrill v. Robert Marsh & Co., Inc., supra, 138 Cal.App. at p. 106), or (2) pursuant to the “revival” provisions of section 3802 for termination of the suspension of the underlying obligation.
In sum, we are of the view that the parties to the 1973 note expressed the intent to retain the original maturity date of the 1972 note; that the underlying character of the 1972 note is preserved notwithstanding the renewal note; and, alternatively, that even if the maturity date was suspended pursuant to section 3802, HHR’s failure to comply with PCA’s demand revived the underlying obligation, including the due date. In any event, execution of the 1973 note ultimately had no effect on the maturity date of the first note. Thus, the maturity [659]*659date on the original obligation remained unmodified or, if suspended pursuant to section 3802, was revived from the time of PCA’s first written demand in March 1974, which, we note, preceded the date respondents made the first of three payments for which they were awarded contribution. We cannot agree, therefore, with respondents’ assertion that the first three notes had identical maturity dates. Although at the time of its first demand PC A was entitled to demand payment on all three notes, we conclude that each note nonetheless retained its respective maturity date.
We therefore hold that the 1972 note was the “earliest in date of maturity” within the meaning of Civil Code section 1479, subdivision Three 3, and that payments made by HER prior to 1975 should properly have been credited first to the payment of the 1972 note. Ead the trial court not erred by apportioning the payments among the four notes, the 1972 note would have been completely extinguished prior to respondents’ post-1975 payments for which they sought contribution. We conclude that reversal is warranted on this issue.
Appellant’s contention that she had an equitable lien on the “Baldwin stock”
Appellant next contends that respondents are not entitled to ownership of the Baldwin stock (the last 350 shares of EER stock obtained by Jessup Farms) because she had an equitable lien on that stock pursuant to the property settlement agreement. Therefore, appellant argues, the trial court erred in finding that Jessup Farms was a bona fide purchaser without notice of her alleged security interest. We disagree.
As noted in our recitation of facts, appellant retained a security interest in the stock she transferred to her husband pursuant to the property settlement agreement. Although this interest was never perfected, appellant nonetheless argues that respondent Jessup Farms had notice of her security interest when it obtained the Baldwin stock from her ex-husband Wayne. Appellant acknowledges that each of the witnesses testifying for respondents on this issue denied receiving any information concerning the security interest prior to Jessup Farms’ acquisition of the Baldwin stock pursuant to the March 19 agreement. The trial court found, on this disputed evidence, that respondents obtained the Baldwin stock without notice or knowledge of any claimed security interest.
Thus, appellant’s second contention—that she has an equitable lien on the stock and that respondents are not bona fide purchasers—is nothing more than an attack on the sufficiency of the evidence to support the trial court’s conclusions that the March 19 option contract is specifically enforceable, and that respondents should take the Baldwin stock free and clear of appellant’s purported security interest. We conclude that the trial court’s findings are supported by substantial evidence.
[660]*660The critical issue here is whether respondents, Jessup Farms or the individual Jessups, are chargeable with constructive notice of the claimed security interest. In this regard, appellant places great reliance on a passage in a letter from counsel for HHR to an Idaho attorney representing Mr. Baldwin. A copy of this letter was sent to one of the senior partners and to the accountant of Jessup Farms. Appellant argues that the receipt of the letter by one of the Jessups compels the conclusion that respondents were on notice of her claimed security interest. The letter itself belies this contention.
The crucial passage, as underscored by appellant herself, is a statement by HHR’s attorney that “. . .it was my instruction as well as those of Webster Jessup, president of the corporation, and Burke Dambley, corporation C.P. A., that the contract [a rescinded redemption agreement not here relevant] was not to be considered properly signed until unconditionally signed by Eileen Baldwin, who has a one-half community property interest in Wayne’s stock in the corporation, ...” (Italics added.) This passage, at most, indicates that at the time the letter was received the Jessups were still operating under the assumption that appellant held a community property interest in the stock, a fact they probably had always assumed. This letter therefore does not persuade us to disturb the trial court’s findings since it in no way supports the conclusion that the Jessups had notice, actual or constructive, that appellant had transferred her community property interest in the stock to Mr. Baldwin pursuant to a property settlement agreement and had taken in exchange a security interest in the stock to secure performance of Mr. Baldwin’s other obligations under the agreement.
Even if we were to draw some inference favorable to appellant from this single evidentiary item, the quoted passage at best creates a conflict in the evidence. The fact that it is possible to. draw some inference other than that drawn by the trier of fact is of no consequence. (Forte v. Nolfi (1972) 25 Cal.App.3d 656, 667 [102 Cal.Rptr. 455].) Where findings of fact are challenged on a civil appeal, we are bound by the “elementary, but often overlooked principle of law, that ... the power of an appellate court begins and ends with a determination as to whether there is any substantial evidence, contradicted or uncontradicted,” to support the findings below. (Crawford v. Southern Pacific Co. (1935) 3 Cal.2d 427, 429 [45 P.2d 183].) We must therefore view the evidence in the light most favorable to the prevailing party, giving it the benefit of every reasonable inference and resolving all conflicts in its favor in accordance with the standard of review so long adhered to by this court. (Ibid.; Bandle v. Commercial Bk. of Los Angeles (1918) 178 Cal. 546, 547 [174 P. 44]; see also Aceves v. Regal Pale Brewing Co. (1979) 24 Cal.3d 502, 507 [156 Cal.Rptr. 41, 595 P.2d 619]; Munoz v. Olin (1979) 24 Cal.3d 629, 635 [156 Cal.Rptr. 727, 596 P.2d 1143]; 6 Witkin, Cal. Procedure (2d ed. 1971) §§ 247, 248, pp. 4239-4240.)
[661]*661Applying this familiar standard of appellate review, we conclude that the challenged findings in this case are supported by substantial evidence—notably the testimony of some of the Jessups and their accountant that they had no knowledge of appellant’s claimed security interest prior to entering into the option contract with Mr. Baldwin. The trial court’s findings are binding on appeal; accordingly, we cannot disturb its conclusion, reached after hearing all the evidence, that respondents had no constructive notice of appellant’s unperfected interest.22 The judgment giving Jessup Farms absolute ownership and possession of the Baldwin stock must be upheld.
HI
For the aforementioned reasons, we reverse that portion of the judgment ordering appellant Eileen Baldwin to make contribution to Jessup Farms. That portion of the judgment ordering specific performance of the option contract between respondents and Wayne Baldwin and denying appellant’s cross-complaint for an equitable lien on the stock transferred pursuant to that contract is affirmed.
Each party shall bear its own costs on appeal.
Bird, C. J., Mosk, J., and Broussard, J., concurred.