California Code, Corporations Code - CORP § 29104

All contracts for the purchase or sale of shares of the capital stock of any corporation or association without any intention on the part of one party to deliver and of the other party to receive the shares, and contemplating merely the payment of differences between the contract and market prices on divers days, shall be void, and neither party to any such contract shall be entitled to recover any damages for failure to perform the same, or any money paid thereon, in any court of this state.