California Code, Civil Code - CIV § 1894

The lender of a thing for use may at any time require its return, even though he lent it for a specified time or purpose.  But if, on the faith of such an agreement, the borrower has made such arrangements that a return of the thing before the period agreed upon would cause him loss, exceeding the benefit derived by him from the loan, the lender must indemnify him for such loss, if he compels such return, the borrower not having in any manner violated his duty.