Opinion for the Court filed by Circuit Judge SPOTTSWOOD W. ROBINSON, III.
Concurring opinion filed by Judge DAVIS.
Dissenting opinion filed by Circuit Judge ROBB.
SPOTTSWOOD W. ROBINSON, III, Circuit Judge:Trustees of the United Mine Workers health and retirement funds have denied permanent health-care coverage to the surviving spouses of two deceased coal miners. The disappointed claimants challenge the denial as arbitrary, and thus as a violation of Section 302(c) of the Labor-Management Relations Act.1 The District Court entered judgment for the trustees, finding dispositive the fact that they had acted in reliance upon eligibility rules derived from “explicit, informed and intense” collective bargaining.2 We hold that the eligibility standards themselves transgress federal law3 and consequently are forbidden, even as the fruits of labor negotiations.4 Accordingly, we reverse.
I
Section 302(c) excepts from a general prohibition against nonsalary payments by employers to employees those which are made into a trust fund to provide the latter with health or retirement benefits.5 The United Mine Workers of America (UMW) first erected such a fund in 1947.6 Three years later it was replaced by the UMW Welfare and Retirement Fund of 1950, created by the National Bituminous Coal Wage Agreement of that year.7 That agreement specified that each coal operator participating in the contract would contribute a designated sum for each ton of coal produced, and that the monies would be used for pension and health-care coverage, but left to the trustees the particularization of eligibility requirements for benefits and the amounts thereof.8
In 1974, pursuant to a new wage agreement, the 1950 fund was replaced by four trusts. Two of them govern only pension payments and so are not at issue here. Of the others, the “1974 Benefit Plan and Trust” provides health-care coverage prospectively for miners retiring after the *333wage agreement became operative on December 6, 1974; and “the 1950 Benefit Trust” replaced the earlier fund with coverage for miners who retired prior to the 1974 date.9 Unlike their immediate predecessor, these, two trusts undertake to limit the trustees’ discretion to set eligibility standards. The 1974 wage agreement itself purports to establish the rules,10 and the trustees are permitted to amend them unilaterally only to ensure compliance with applicable federal laws.11
Floyd Robinson and Paul C. Hager were active miners who died before the new trusts were adopted. Both were qualified for pensions by age and length of service, but chose instead to continue working and thus had not retired before their deaths.12 Appellants, their widows, became eligible, as survivors of working miners, to receive approximately five years of health benefits from the fund then in effect.13 A surviving spouse of an already retired miner was entitled to about two years of coverage.14
Several years later the 1974 wage agreement was adopted. It lengthened the period of benefits eligibility for at least some surviving spouses and dependents. The 1950 Benefit Trust extends permanent health-care coverage to the unmarried spouse and dependents of “a miner who dies .. . [p]rior to the effective date of this Plan15 ... at a time when he was receiving a retirement or disability pension under the eligibility rules” of the predecessor fund.16 By the trustees’ interpretation, this clause applies to survivors of miners who died while collecting pensions and, as well, to survivors of those who, though not actually receiving retirement payments at death, had ceased work and applied for them.17 This construction, however, excludes widows and dependents of those miners who were eligible for pensions but who continued working and later died before applying for health-care benefits.18 No such distinction is made in the terms of the 1974 Benefit Plan and Trust; survivors of those dying *334after December 6, 1974, will receive permanent benefits whether or not retirement actually occurred prior to death.19
Appellants were refused permanent health-care coverage because their husbands worked until their deaths, respectively, in 1967 and 1971. On behalf of themselves and all others similarly situated, appellants sued in the District Court, charging that the trustees, by denying them such benefits, had acted arbitrarily and had violated their fiduciary duties, all in contravention of Section 302(c) of the Labor-Management Relations Act.20 During the course of the proceedings, the court ruled that appellants had made a showing of arbitrariness sufficient to shift the burden of proof to the trustees, and that in the absence of further evidence apellants would be granted summary judgment.21
The trustees thereupon submitted documents and oral testimony pertaining to the conduct of the labor negotiations that culminated in the 1974 wage agreement containing the eligibility rules under which they had acted.22 The court held that this evidence effectively rebutted appellant’s prima facie case by establishing that the decision to exclude the appellant class from permanent health benefits was a rational choice consciously made by the participants in the collective bargaining.23 The court accordingly entered judgment for the trustees, and this appeal followed.
II
Our analysis must begin with an inquiry into the nature of the restrictions statutorily imposed on employee trust funds. Section 302(c) requires that the trusts be maintained “for the sole and exclusive benefit of the employees of [the contributing] employer, and their families and dependents.”24 It also requires that payments be made only for medical care, pensions, compensation for occupational injuries and other like purposes.25 While these statutory provisions leave trustees with broad discretion to choose among rational alternatives in setting eligibility standards,26 this court has long held that, because Section 302(c) casts authority to establish benefit programs in fiduciary terms, it forbids arbitrary or capricious decisions by those who administer the funds.27 We have thus construed this section as demanding at least that the trustees’ actions be procedurally fair28 and that *335their factual judgments be based on substantial evidence.29 Beyond this, however, we have consistently held that Section 302(c) also imposes substantive limitations on the nature of the eligibility rules that may be selected.30 We summarize our reading on the latter score for the assistance it offers to resolution of the issue at bar.
Section 302(c), we repeat, requires trust funds to be held “for the sole and exclusive benefit of the employees of [the contributing] employer.” 31 Any rule denying benefits to miners on whose behalf significant contributions to a pension fund have been made appears on its face to contravene this statutory command; and thus calls for satisfactory explanation.32 This is particularly true if, at the same time, the rule grants benefits to others who have worked a considerably lesser period of time for contributing employers.33 In all such circumstances, we have insisted that the trustees demonstrate some “rational nexus between the Fund’s purpose and the [eligibility] requirement.”34 Standards producing otherwise arbitrary discrepancies may be acceptable where the rule discourages workers from taking voluntary action that shifts the burden of supporting the fund to other employees, for instance by retiring early,35 by leaving the industry,36 or by working for noncontributing employers.37 Correspondingly, a differential is permissible when it rewards substantial service rendered employers who assist in maintaining the trust fund.38
What we must determine, then, is whether the rules challenged here meet the substantive demands of Section 302(c). Our task is made easier because the District Court expressly held, before receiving evidence describing the collective bargaining process from which the provision emerged, that the new eligibility standards appeared sufficiently arbitrary to compel judgment for the appellant class in the absence of *336further explanation.39 None of the rationales offered had convinced the court that the restriction on eligibility complained of reasonably related to the fund’s purpose, nor do they satisfy us. We must add, moreover, that we do not find the subsequent presentation to the court any more persuasive.
Like others that we have been forced to overturn,40 the eligibility rules contested here exclude from permanent health-care coverage survivors of miners with substantial histories of contributory employment, while conferring that coverage on survivors of miners with appreciably less signatory employment. Appellants were themselves denied permanent health benefits despite more than 21 years of signatory employment by each of their husbands.41 Contrastingly, the eligibility rules qualify survivors of miners with as little as one year of contributory service for permanent coverage so long as their husbands actually retired before death.42 The facial inequity of this arrangement is further highlighted by the fact that the husband of one appellant died five days after reaching age 55, having met all requirements and intending to retire but failing to do so within the short period elapsing after his birthday.43 Additionally, the rules reward those early retirees for whom no further contributions are made into the health-benefit fund. Such a course is surely questionable in terms of statutory purpose.44
Nonetheless, the eligibility standards applied by the trustees could have passed muster had they been shown to be rationally related to the fund’s purposes.45 We find no such proof, however. The trustees relied on the fact that they adopted the challenged eligibility rules not as in bygone days under broad authority granted them in collectively-bargained agreements, but at the specific direction of union and management representatives negotiating the 1974 wage agreement.46 The District Court accepted this explanation as adequate justification,47 and we too are sympathetic toward a compromise hammered out by “explicit, informed and intense” bargaining on a problem difficult of resolution in a mutually acceptable manner.48 But, as we have already seen, Section 302(c) sets substantive limits on the rules established for employee trust funds;49 as a consequence who formulated the eligibility standards and how it was done are irrelevancies. What is essential is that the eligibility rules themselves not be arbitrary or capricious in content when measured against the governing statute.
We hold that exclusion of the appellant class from permanent health-care cov*337erage was arbitrary.50 That it was the deed of labor-contract negotiators rather than fund trustees does not excuse it.51 The Act does not permit bargainers to engage in discriminatory conduct forbidden to trustees; indeed, the statutory provisions operative here were designed especially to control abuses in the collective bargaining process.52 We ourselves have read the Act as imposing curbs on eligibility definitions in pension plans despite the “presum[ption] that management and labor would agree on pension eligibility requirements.”53 Were we to find rationality in every rule arising from “explicit, informed and intense” bargaining,54 we would establish a sure means of circumventing statutory restrictions on the entire front of employee trust funds.
Of course, the negotiators may select eligibility rules so long as they can advance an adequate explanation for their action. The only reason appearing on the record, however, is that the bargainers sought to eliminate an additional drain on the fund’s resources in order to peg employer contributions at a mutually agreeable level.55 But “financial considerations by themselves should not be sufficient justification for an exclusive eligibility requirement as every exclusive eligibility requirement would have the virtue of saving money.” 56 To be sure, actuarial soundness is of legitimate concern to a fund’s trustees,57 *338but financial integrity must be secured by methods dividing beneficiaries from nonbeneficiaries on lines reasonably calculated to further the fund’s purposes. It is not enough that the particular eligibility standards were adopted simply because that enabled resolution of a collective bargaining dispute.
After ample opportunity, no legally acceptable justification for exclusion of the appellant class from permanent health-care benefits has been proffered. It follows that the eligibility rules achieving that end must fall. The judgment appealed from is reversed and the case is remanded to the District Court for determination of the relief properly to be afforded.
So ordered.
. Labor Management Relations Act of 1947, § 302(c), 29 U.S.C. § 186(c) (1976) [hereinafter cited as codified],
. Robinson v. UMW Health & Retirement Funds, Civ. No. 77-0698 (D.D.C. June 20, 1978), at 1, Joint Appendix (J. App.) 95.
. See text infra at notes 24-44.
. See text infra at notes 45-57.
. 29 U.S.C. § 186(c) (1976) reads in relevant part:
The provisions of this section [forbidding transfers between employer and employees] shall not be applicable ... (5) with respect to money or other things of value paid to a trust fund established by such representative, for the sole and exclusive benefit of the employees of such employer, and their families and dependents (or of such employees, families, and dependents jointly with the employees of other employers making similar payments, and their families and dependents): Provided, That (A) such payments are held in trust for the purpose of paying, either from principal or income or both, for the benefit of employees, their families and dependents, for medical or hospital care, pensions on retirement or death of employees, compensation for injuries or illness resulting from occupational activity or insurance to provide any of the foregoing, or unemployment benefits or life insurance, disability and sickness insurance, or accident insurance; (B) the detailed basis on which such payments are to be made is specified in a written agreement with the employer, and employees and employers are equally represented in the administration of such fund, together with such neutral persons as the representatives of the employers and the representatives of employees may agree upon . .. and (C) such payments as are intended to be used for the purpose of providing pensions or annuities for employees are made to a separate trust which provides that the funds held therein cannot be used for any purpose other than paying such pension or annuities ....
. See generally Van Horn v. Lewis, 79 F.Supp. 541 (D.D.C. 1948).
. Record on Appeal (R.) 4, Appendix (App.) C (National Bituminous Coal Wage Agreement of 1950).
. Id. at 4:
Subject to the stated purposes of this Fund, the Trustees shall have full authority, within the terms and provisions of the “Labor-Management Relations Act, 1947,” and other applicable law, with respect to questions of coverage and eligibility, priorities among classes of benefits, amounts of benefits, methods of providing or arranging for provisions for benefits, investment of trust funds, and all other related matters.
. R. 4, App.D (National Bituminous Coal Wage Agreement of 1974) at 27.
. Id. at 31-33.
. Id. at 31:
The Trustees are authorized, upon approval by the Employers and the Union, to make such changes in the Plans and Trusts hereunder as they may deem to be necessary or appropriate.
They are also authorized and directed, after adequate notice and consultation with the Employers and Union, to make such changes in the Plans and Trusts hereunder, including any retroactive modification or amendments, which shall be necessary:
(a) to conform the terms of each Plan and Trust to the requirements of ERISA, or any other applicable federal law ....
(d) to comply with all applicable court or government decisions or rulings.
. When Floyd Robinson died in 1967, pension eligibility was governed by Resolution 63, which required 20 years of employment, attainment of age 55 and one year of “signatory” or “contributory” service — work for an employer who is a signatory to the pension agreement— immediately prior to retirement. Robinson’s death occurred five days after his 55th birthday, while he was working for a signatory employer and after he had completed 25 years of industry employment, including 21 years of contributory service. J.App. 73-75. At the time of Paul C. Hager’s death in 1971, Resolution 83 was in force; it required 20 years of service, attainment of age 55, and a total of five years of contributory employment with one year immediately prior to retirement. Hager had been credited with 24 years of service, all of which was with signatories, and was an active miner at the time of his death. Indeed, Hager had retired for a short period in 1968, but had resumed work because he was unable to support his family and himself on his pension. J.App. 76-78.
. When each died, Resolutions 68 and 69 specified the survivor’s and health-care benefits due their widows. The surviving spouse of an active miner was to receive a survivor’s benefit of $5,000 over a five-year period, and the widow of a retired miner a benefit of $2,000 over two years. R. 4, App. A (Resolution 68). Each was then entitled to health-care assistance while the survivor’s benefit was payable. R. 4, App. B (Resolution 69).
. See note 13 supra.
. See text supra at note 9.
. J.App. 26 (emphasis supplied).
. R. 53.
. Id.
. See note 42 infra.
. See Brief for Appellants at 4.
. Robinson v. UMW Health & Retirement Funds, 449 F.Supp. 941, 945 (D.D.C. 1978).
. See J. App. 98-211 (transcript of proceedings).
. Robinson v. UMW Health & Retirement Funds, supra note 2, at 1, J. App. 95.
. 29 U.S.C. § 186(c) (1976), quoted in pertinent part supra note 5.
. Id. The relevant portions of the statute are quoted at length in note 5 supra.
. E. g., Pete v. UMW Welfare & Retirement Fund of 1950, 171 U.S.App.D.C. 1, 9, 517 F.2d 1275, 1283 (en banc 1975); Roark v. Boyle, 141 U.S.App.D.C. 390, 392, 439 F.2d 497, 499 (1970); Johnson v. Botica, 537 F.2d 930, 935 (7th Cir. 1976); Lee v. Nesbitt, 453 F.2d 1309, 1311 (9th Cir. 1971).
. Pete v. UMW Welfare & Retirement Fund of 1950, supra note 26, 171 U.S.App.D.C. at 9, 517 F.2d at 1283; Roark v. Boyle, supra note 26, 141 U.S.App.D.C. at 392, 439 F.2d at 499; Gaydosh v. Lewis, 133 U.S.App.D.C. 274, 277, 410 F.2d 262, 265 (1969); Roark v. Lewis, 130 U.S.App.D.C. 360, 362, 401 F.2d 425, 427 (1968); Kosty v. Lewis, 115 U.S.App.D.C. 343, 346, 319 F.2d 744, 747 (1963), cert. denied, 375 U.S. 964, 84 S.Ct. 482, 11 L.Ed.2d 414 (1964); Danti v. Lewis, 114 U.S.App.D.C. 105, 108 & n.3, 312 F.2d 345, 348 & n.3 (1962).
.In Kosty v. Lewis, supra note 27, the trustees had altered the eligibility rules to require that the 20 years of service already prerequisite to a pension be rendered during the 30 years immediately preceding retirement. We held the change arbitrary and capricious in its effect on miners who met the old but not the new standard, since they were not given notice of the change and thus were unable to elect retirement before the new rule became effective and abrogated their pension eligibility. 115 U.S.App.D.C. at 347-348, 319 F.2d at 748-749. Absent any form of notification, we said, the modification lacked the fundamental fairness demanded of those with fiduciary responsibilities. Id. Similarly, in Danti v. Lewis, supra note 27, we rejected as procedurally flawed a decision to deny benefits because the miner’s pension *335application did not demonstrate compliance with an eligibility standard adopted after it was filed, but before it was acted upon, since he thus was afforded no opportunity to show that he qualified under the amended rule. 114 U.S.App.D.C. at 109 n.4, 312 F.2d at 349 n.4.
. Danti v. Lewis, supra note 27, 114 U.S.App.D.C. at 108-109, 312 F.2d at 348-349.
. See cases cited infra notes 32-38.
. 29 U.S.C. § 186(c) (1976), quoted in pertinent part supra note 5.
. Norton v. I.A.M. Nat’l Pension Fund, 180 U.S.App.D.C. 176, 181-182, 553 F.2d 1352, 1357-1358 (1977), Roark v. Lewis, supra note 27, 130 U.S.App.D.C. at 363, 401 F.2d at 428.
. Before us in Roark v. Lewis, supra note 27, was an eligibility standard prescribing that a miner must have 20 years of service but must also have retired immediately after a period of work for a signatory — the so-called “signatory last employment” rule — regardless of the total length of contributory employment. We found a prima facie showing of unreasonableness in a demonstration that under this requirement “employees could spend .. . practically their entire adult lives working for mine, owners who had contributed to the Fund since its inception; yet if they were to work for a non-signatory operator for any period after leaving a signatory operator, they would forfeit their otherwise valid pension claims.” In sharp contrast, other miners could have worked 19 years for a noncontributing employer and get gain eligibility by only a year of signatory work. 130 U.S.App.D.C. at 363, 401 F.2d at 428. In Norton v. I.A.M. Nat’l Pension Fund, supra note 32, the pension agreement specified that should a signatory employer withdraw from participation, all service credits for his employees would be cancelled, including any earned while contributions were being made. We found it unnecessary to decide whether this provision was per se unreasonable, but we noted the similarity of its effects to those of the provision in Roark. 180 U.S.App.D.C. at 181-182, 553 F.2d at 1357-1358. The rule here involved has analogous consequences. See text infra at notes 41—44.
. Roark v. Lewis, supra note 27, 130 U.S.App.D.C. at 364, 401 F.2d at 429.
. See Gaydosh v. Lewis, supra note 27, 133 U.S.App.D.C. at 277, 410 F.2d at 265.
. See Assalone v. Carey, 154 U.S.App.D.C. 69, 73 & n.2, 473 F.2d 199, 203 & n.2 (1972); Giler v. Board of Trustees of Sheet Metal Workers Pension Plan, 509 F.2d 848, 849 (9th Cir. 1974).
. See Roark v. Lewis, supra note 27, 130 U.S.App.D.C. at 364, 401 F.2d at 429.
. Pete v. UMW Welfare & Retirement Fund of 1950, supra note 26, 171 U.S.App.D.C. at 12-13, 517 F.2d at 1286-1287.
. Robinson v. UMW Health & Retirement Fund, supra note 21, 449 F.Supp. at 945.
. See notes 32-38 supra.
. See note 12 supra.
. This anomaly was produced by the provision, in effect at the time of Floyd Robinson’s death, which demanded 20 years of industry employment but only one year of . signatory service, although that one year must have been immediately prior to retirement. J.App. 73-75. We struck down the one-year signatory-last-employment requirement in Roark v. Boyle, supra note 26, 141 U.S.App.D.C. at 401, 439 F.2d at 508. Although under the rules presently operative, a miner still needs only five years of contributory service, see Pete v. UMW Welfare & Retirement Fund of 1950, supra note 26, 171 U.S.App.D.C. at 9, 517 F.2d at 1283, the disparity in widows’ benefits at issue here cannot occur with respect to miners who retire or die after 1974 because the 1974 Benefit Plan and Trust provides permanent health-care coverage prospectively to surviving spouses of all pension-eligible miners, whether or not they retired before death. R. 17, at 4.
. See note 12 supra.
. See text supra at notes 30-33.
. See text supra at notes 34-38.
. See Robinson v. UMW Health & Retirement Funds, supra note 2, at 1, J.App. 95.
. Id.
. See text supra at notes 2, 22-23, infra at note 55.
. See notes 30-38 supra and accompanying text.
. See text supra at notes 39-44.
. See Toensing v. Brown, 528 F.2d 69, 72 (9th Cir. 1975):
[T]rustees have a duty to exercise their independent judgment in administering trust funds established under § 302 of the Labor Management Relations Act. Recommendations of collective bargaining parties may be adopted by the trustees in the exercise of their discretion, but such recommendations are not binding or obligatory.
The situation would be different had the negotiators themselves acted on grounds reasonable in light of the requirements of Section 302(c). But we find no acceptable explanations, see text infra at notes 55-57, and in the absence thereof the trustees cannot be allowed to pursue eligibility standards solely because the bargainers agreed to them. That this court has power to review the constitutional and statutory legality of substantive terms of a collective bargaining agreement is beyond dispute. See, e.g., NLRB v. Magnovox Co., 415 U.S. 322, 325-327, 94 S.Ct. 1099, 1102-1103, 39 L.Ed.2d 358, 362-363 (1974); Brotherhood of R.R. Trainmen v. Howard, 343 U.S. 768, 773-775, 72 S.Ct. 1022, 1025-1026, 96 L.Ed. 1283, 1288-1289 (1952); Steele v. Louisville & N.R.R., 323 U.S. 192, 199-202, 65 S.Ct. 226, 230-232, 89 L.Ed.2d 173, 181-183 (1944).
. Arroyo v. United States, 359 U.S. 419, 424-427, 79 S.Ct. 864, 867-869, 3 L.Ed.2d 915, 919-920 (1959); Mosley v. National Maritime Union Pension & Welfare Plan, 438 F.Supp. 413, 421 (E.D.N.Y.1977) (“an important purpose of [§ 302(c)] was to protect employees from the collusion of union officials and management”). True it is, as the District Court here stated, that “[p]ublic policy dictates the limited role of courts in reviewing collectively bargained agreements.” Robinson v. UMW Health & Retirement Funds, supra note 2, at 2, J.App. 97. But the history of employee trusts warns that neither labor nor management can be counted on invariably to represent fully and fairly the employees’ interests therein. Blind deference is thus unsafe in reviewing the § 302(c) claims pressed here whether or not, as appellants allege, there was any bad faith on the part of the union negotiators. See Brief for Appellants at 23-24.
. Pete v. UMW Welfare & Retirement Fund of 1950, supra note 26, 171 U.S.App.D.C. at 12, 517 F.2d at 1286. Indeed, § 302(c) requires that “the detailed basis on which [benefits] payments are to be made [be] specified in a written agreement with the employer,” 29 U.S.C. § 186(c)(5)(B) (1976), and that agreement is almost certain to be bottomed on collective bargaining. Moglia v. Geoghegan, 267 F.Supp. 641, 646 (S.D.N.Y. 1967), aff'd, 403 F.2d 110 (2d Cir. 1968), cert. denied, 394 U.S. 919, 89 S.Ct. 1193, 22 L.Ed.2d 453 (1969).
. See Robinson v. UMW Health & Retirement Funds, supra note 2, at 1, J.App. 95.
. See, e. g., J.App. 126-128, 133-134, 147-149, 184-185.
. Fase v. Seafearers Welfare & Pension Plan, 432 F.Supp. 1037, 1041 (E.D.N.Y.1977), aff’d, 589 F.2d 112 (2d Cir. 1978).
. Roark v. Boyle, supra note 26, 141 U.S.App.D.C. at 394, 439 F.2d at 501; Roark v. Lewis, supra note 27, 130 U.S.App.D.C. at 364, 401 F.2d at 429.
The record leaves unclear the financial impact of including the appellant class. There was testimony that the union negotiators felt that there might be an additional 4,000 widows, out of a total population of 40,000, who would thereby receive health benefits, but precise figures were unavailable. J.App. 125. Other testimony suggested the number might be less. J.App. 181, 190-191. The District Court concluded that “[b]oth sides recognized that the magnitude of the [appellant] class could not be practicably determined.” Robinson v. UMW Health & Retirement Funds, supra note 2, at 1, *338J.App. 96. We note, however, that the class is not open-ended, as it includes only survivors of miners who qualified for pensions but died before December 6, 1974, while still in active service. See text supra at notes 15-19.