Section 300.503 - Voidable securities transactions(a) Nothing in these Series 500 Rules shall be construed as limiting the rights of a trustee in a liquidation proceeding under the Act to avoid any securities transaction as fraudulent, preferential, or otherwise voidable under applicable law.(b) Nothing in these Series 500 Rules shall be construed as limiting the right of the Securities Investor Protection Corporation, in a direct payment procedure under section 10 of the Act, to reject a claim for cash or a claim for securities if such claim arose out of a securities transaction which could have been avoided in a liquidation proceeding under the Act.