In Marvin v. Marvin (1976) 18 Cal. 3d 660, the California Supreme Court held that "a nonmarital partner" should be permitted "to assert rights based upon accepted principles of implied contract or equity." (Marvin, supra, 18 Cal.3d at p. 682.) "The parties to a nonmarital relationship may well expect that property will be divided in accord with the parties' own tacit understanding and that in the absence of such understanding the courts will fairly apportion property accumulated through mutual effort. We need not treat nonmarital partners as putatively married persons in order to apply principles of implied contract, or extend equitable remedies; we need to treat them only as we do any other unmarried persons." (Marvin, at p. 682.)