California Code, Family Code - FAM § 3763

(a) The health insurance coverage assignment order may be ordered at the time of trial or entry of a judgment ordering health insurance coverage. The order operates as an assignment and is binding on any existing or future employer of the obligor parent, or other person providing health insurance to the obligor, upon whom a copy of the order has been served.

(b) The order of assignment may be modified at any time by the court.