Subject to subsection (d), in any civil action alleging a violation of section 1 or 3 of this title, or alleging a violation of any similar State law, based on conduct covered by a currently effective antitrust leniency agreement, the amount of damages recovered by or on behalf of a claimant from an antitrust leniency applicant who satisfies the requirements of subsection (b), together with the amounts so recovered from cooperating individuals who satisfy such requirements, shall not exceed that portion of the actual damages sustained by such claimant which is attributable to the commerce done by the applicant in the goods or services affected by the violation.