40 C.F.R. § 35.6600
(b) Claims settlement. The recipient may incur costs (including legal, technical and administrative) to assess the merits of or to negotiate the settlement of a claim by or against the recipient under a contract, provided:
(c) Claims defense. The recipient may incur costs (including legal, technical and administrative) to defend against a contractor claim for increased costs under a contract or to prosecute a claim to enforce a contract provided: