Traditionally, courts have recognized that claims for implied contractual indemnity and tort-based indemnity arise from different sources--a contractual duty between the proposed indemnitee and indemnitor for the former, and a tort duty to the underlying plaintiff for the latter. (Compare, e.g., Great Western Furniture Co. v. Porter Corp (1965) 238 Cal. App. 2d 502, 516-517 implied contractual indemnity and Columbus Line, supra, 120 Cal. App. 3d 622, 628 tort-based indemnity.) In Bear Creek Planning Com. v. Title Ins. & Trust Co. (1985) 164 Cal. App. 3d 1227, the court explained: "An action for implied contractual indemnity is not a claim for contribution from a joint tortfeasor; it is not founded upon a tort or upon any duty which the indemnitor owes to the injured third party. It is grounded upon the indemnitor's breach of duty owing to the indemnitee to properly perform its contractual duties." (Id. at pp. 1238-1239.) See also Smoketree-Lake Murray, Ltd. v. Mills Concrete Construction Co. (1991) 234 Cal. App. 3d 1724, 1736-1737 "Implied contractual indemnity is applied to contract parties and is designed to apportion loss among contract parties based on the concept that one who enters a contract agrees to perform the work carefully and to discharge foreseeable damages resulting from that breach.".) The Bear Creek court took this distinction one step further, however, and found that "implied contractual indemnity is not based upon equitable considerations." (Bear Creek, at p. 1239.) Thus, the court concluded, the defendant in an action for implied contractual indemnity is not entitled to an apportionment of damages based on theories of equitable indemnity and the comparative fault principles of American Motorcycle. (Id. at p. 1240.) In Bay Development, Ltd. v. Superior Court (1990) 50 Cal.3d 1012, the California Supreme Court disapproved of Bear Creek to the extent it held that a claim for implied contractual indemnity is not a form of equitable indemnity and is not subject to equitable apportionment principles. (Bay Development, supra, 50 Cal.3d 1012, 1031-1032 & fn. 12.) The court thus concluded that "a claim based on an implied contractual indemnity theory is a form of equitable indemnity, and therefore such a claim is barred by a good faith settlement under Code of Civil Procedure section 877.6, subdivision (c)." (Id. at p. 1020.)