People sometimes build a business together without forming a company or signing a detailed joint-venture agreement. When the business succeeds and the relationship breaks down, the absence of formal paperwork can become a major issue.
California law recognizes that a joint venture may, in appropriate circumstances, be formed orally or inferred from the parties’ acts and declarations. Weiner v. Fleischman (1991) 54 Cal.3d 476, 482–483.
But working together on a business opportunity does not necessarily create a joint venture.
What Does a Court Look For?
California courts have described a joint venture as an undertaking by two or more persons to jointly carry out a business enterprise for profit. Relevant considerations include whether the parties had a joint interest in the undertaking, an understanding concerning profits and losses, and a right of joint control. April Enterprises, Inc. v. KTTV (1983) 147 Cal.App.3d 805, 819.
The evidence can therefore matter as much as the label the parties used.
Communications about ownership and profit sharing, records of financial contributions, evidence of services performed, dealings with customers, and evidence showing who exercised control over the business may bear on whether the claimed relationship actually existed.
Does It Have to Be Written?
Sometimes.
Civil Code section 1622 generally permits oral contracts, but Civil Code section 1624 requires certain agreements to be in writing. In Clarke v. Yu (2026), the California Court of Appeal applied the statute of frauds to an alleged oral joint venture that, by its terms, could not be performed within one year.
The result therefore depends on what the parties actually agreed to, not simply whether they called themselves partners or joint venturers.
Authorities: Cal. Civ. Code §§ 1622, 1624; Weiner v. Fleischman (1991) 54 Cal.3d 476; April Enterprises, Inc. v. KTTV (1983) 147 Cal.App.3d 805; Clarke v. Yu (2026).
Related practice areas: Corporate Governance & Shareholder Disputes · Civil Litigation