Pub. Contract Code, § 10194

(a) If the department elects to award a project pursuant to this article, retention proceeds withheld by the department from the design-build entity shall not exceed 5 percent if a performance and payment bond, issued by an admitted surety insurer, is required in the solicitation of bids.

(b) In a contract between the design-build entity and a subcontractor, and in a contract between a subcontractor and any subcontractor thereunder, the percentage of the retention proceeds withheld may not exceed the percentage specified in the contract between the department and the design-build entity. If the design-build entity provides written notice to any subcontractor that is not a member of the design-build entity, prior to or at the time the bid is requested, that a bond may be required and the subcontractor subsequently is unable or refuses to furnish a bond to the design-build entity, then the design-build entity may withhold retention proceeds in excess of the percentage specified in the contract between the department and the design-build entity from any payment made by the design-build entity to the subcontractor.