concurring:
I join the majority’s retroactivity holding as well as its holdings declaring the double payment regulation (42 C.F.R. § 411.24(i)), the mandatory notice regulation (42 C.F.R. § 411.25(a)) and the carve out coverage regulation (42 C.F.R. § 411.32(a)®) valid and the claims filing regulation (42 C.F.R. § 411.-24©) and third-party liability regulation (42 C.F.R. § 411.24(e)) invalid. I write separately, however, because I disagree with the majority’s analysis of the third-party liability regulation.
HCFA promulgated the regulation setting forth third-party liability, 42 C.F.R. § 411.-24(e), as an interpretation of the MSP statute. The majority opinion concludes that the regulation is invalid because it is not a rea*426sonable interpretation of the statute. Majority Opinion at 416-17. While I reach the same result, I would invalidate the regulation because it is inconsistent with the plain text of the MSP statute. See Chevron U.S.A, Inc. v. Natural Resources Defense Council, Inc., 467 U.S. 837, 842-43, 104 S.Ct. 2778, 2782, 81 L.Ed.2d 694 (1984).
The MSP statute grants HCFA recourse if it mistakenly pays the health care expenses of an individual covered by both Medicare and an employer group health plan (EGHP). HCFA’s erroneous payments are deemed “conditioned on reimbursement,” 42 U.S.C. § 1395y(b)(2)(B)(i), if the agency determines that payment for the services “has been or could be made” by a third-party payer pursuant to an EGHP. 42 U.S.C. § 1395y(b)(2)(A)(i). To effectuate HCFA’s right of reimbursement, the statute creates a right of action “against any entity which is required or responsible ... to pay ... under a primary plan.” 42 U.S.C. § 1395y(b)(2)(B)(ii). HCFA interprets section 1395y(b)(2)(B)(ii) to grant the United States a direct action against “an employer, an insurance carrier, plan, or program, and a third party administrator.” 42 C.F.R. § 411.24(e). Its interpretation, however, is inconsistent with the text of the MSP statute because the statute creates a right of action only against those entities “required or responsible ... to pay” health care benefits and a third-party administrator (TPA) does not fall within this category.
A TPA is a company that services an employer with a self-insured health plan. Ami-cus Curiae Brief of the Self-Insurance Institute of America at 10-11. A typical contract between the employer and the TPA obliges the TPA to provide elaimsvprocessmg and other administrative services to the employer for a fee. See Joint Appendix (J.A.) at 290-98. Customarily, all health care benefits under the EGHP are paid by the TPA from the employer’s funds; the TPA does not make any payment with its own money nor does it commingle plan funds with its own funds. Amicus Curiae Brief of the Self-Insurance Institute of America at 12. Under its agreement with a self-insured employer, then, the TPA is not “required or responsible” to pay the medical expenses of individuals covered by the EGHP it administers.
Nor does the language of the MSP statute impose a “require[ment]” or “responsibfility]” on the TPA to pay health care expenses. See United States v. Travelers Ins. Co., 815 F.Supp. 521, 524 (D.Conn.1992) (plain language of statute does not impose additional obligations on TPA); Provident Life & Accident Ins. Co. v. United States, 740 F.Supp. 492, 504 (E.D.Tenn.1990) (plain language of statute creates cause of action against only those entities with ultimate responsibility for payment); United States v. Blue Cross & Blue Shield of Michigan, 726 F.Supp. 1517, 1521-22 (E.D.Mich.1989) (statute’s plain text creates right of action only against “those who are responsible to actually make the payments, i.e., the self-insured employer plan ‘itself, and not those who merely undertake to administer the payment process_”). Because the TPA is not obligated to pay health care expenses under either its contract with the employer or the MSP statute and because the right of action created by Congress lies only against an entity obligated to pay, I would invalidate the regulation because it contradicts the “unambiguously expressed intent of Congress.” Chevron U.S.A, Inc. v. Natural Resources Defense Council, Inc., 467 U.S. 837, 842-43,104 S.Ct. 2778, 2782, 81 L.Ed.2d 694 (1984).
The majority believes the statute is ambiguous, and thus open to interpretation by HCFA, because it creates a right of action against an entity not only “responsible” to pay but also “required” to pay. It explains that “[tjhese requirements of course include not only what the employer and employees may have agreed on, but also on the substantive enlargements mandated by the MSP statute itself via its nondiscrimination provisions and its bans on ‘taking into account’ Medicare coverage.” Majority Opinion at 416. From this explication it concludes that the TPA is literally required by the MSP statute to pay for services rendered to Medicare beneficiaries under the plan. Id. It then goes on to invalidate the regulation as an unreasonable interpretation of the statute. But I reject the majority’s statutory exegesis and would instead hold that the agency is not *427free to interpret the plain meaning of the statutory language at all..
As the majority points out, the MSP statute expressly alters the insurer’s obligations to its insured through at least two provisions. See 42 U.S.C. § 1395y(b)(1)(A)(i)(I) (EGHP may not take into account employee’s eligibility for Medicare); 42 U.S.C. § 1395y(b)(1)(A)(i)(II) (EGHP must provide employee age sixty-five or older with same benefits it provides employee under sixty-five). These provisions, however, do not in any way alter the obligations of the TPA to an employee who is covered by the EGHP it administers. Although the majority points to these two statutory provisions as proof positive that the MSP statute enlarges the TPA’s responsibilities, it cannot identify any language in the MSP statute that supports its conclusion. Given Congress’s explicit grant of a right of action against only those entities responsible or required to pay — which a TPA plainly is not — and in the absence of any language in pari materia indicating otherwise, I would hold the regulation invalid' as contrary to the MSP statute’s plain text.*
That the MSP statute plainly intends to allow recovery only from an insurer finds further support in the language of 42 U.S.C. § 1395y(b)(3)(A), which creates a private cause of action for double damages "in the case of a primary plan which fails to provide for primary payment_” Id. (emphasis added). This language evidences Congress’s intent that only the entity that provides a primary plan incur liability. Congress’s use of the term “primary plan” instead of "entily,” as in 42 U.S.C. § 1395y(b)(2)(B)(ii), is not consistent with an intent to impose liability on an entity whose duties with respect to the plan are ministerial only.