California Family Code § 3651 (d)

Definition

The provisions of any agreement for the support of either party shall be deemed to be separate and severable from the provisions of the agreement relating to property. All orders for the support of either party based on such agreement shall be deemed law-imposed and shall be deemed made under the power of the court to make such orders. The provisions of any agreement or order for the support of either party shall be subject to subsequent modification or revocation by court order, except to the extent that any written agreement specifically provides to the contrary.