Cal. Public Contract Code § 10163

The department shall adopt and apply a uniform system of rating bidders, on the basis of the standard questionnaires and financial statements, in respect to the size of the contracts upon which each bidder is qualified to bid. When bids for more than one project are to be received at the same bid opening, the department may permit a bidder to submit bids for each project within such bidder’s prequalification rating, even though such rating is insufficient to permit the bidder to be awarded the contract for each project bid upon. In no event shall any bidder be awarded a contract if such contract award would result in the bidder having under contract work for which prequalification is required in excess of that authorized by his prequalification rating. In determining whether an award of a contract would result in a bidder having under contract work in excess of that authorized by his prequalification rating, the department may use its estimated cost of such contract rather than the amount of the bidder’s bid. If the department determines that a bidder would be awarded the contract for two or more projects but cannot be awarded the contract for all such projects because of the inadequacy of his prequalification rating, the department shall determine which of the bids of such bidder are to be accepted and the contract awarded thereon and which of the bids of such bidder are to be disregarded. In making its decision the department shall be guided by the combination of contract awards which will result in the lowest total cost for the projects involved.