I assume, as does the court, that our review is limited to determining “whether the Trustees have acted arbitrarily, capriciously or in bad faith.” I think the court has exceeded this limit.
Danti filed his application for a pension on September 10, 1952. The Trustees first denied Danti’s application on February 26, 1953, on the ground that he had failed to meet a requirement which was then in effect, but which had not been in effect at the time he filed his application. There has been no allegation that Danti was not permitted adequate opportunity to show that he qualified under the new standard. Thus, the only issue raised by the first denial is whether the retroactive application of revised qualifications is in itself arbitrary.
On May 29, 1957, the Trustees again denied Danti’s application, this time on the ground that he had not met the Trustees’ eligibility requirement (which was in effect both at the time of denial and the time of application) that a worker must have “retired by permanently ceasing work in the Bituminous Coal Industry after May 28, 1946.” 1 The letter of denial stated that: “Since Mr. Danti did not work in the .coal industry after March 1, 1946, his application for pension was necessarily denied.” 2 There is-no dispute over the facts that Danti completed his last day of actual work in the coal industry on March 1, 1946, suffered' a heart attack on March 3, 1946, and' made unsuccessful efforts until1 June of' 1946 to find employment consistent with his health condition. Again there is no claim that Danti was denied an opportunity to show that he qualified under this standard.3 Thus the only issue is whether the Trustees acted arbitrarily or capriciously when they construed “retired by permanently ceasing work” to-refer to the last day of actual work rather that the day on which the worker ceased his efforts to find work.4
Whether revised standards of eligibility are to be applied retroactively, and' whether “retired by permanently ceasing work” means the last day of actual work, are both precisely the kind of question. *352which the National Bituminous Coal Wage Agreement of 1950 5 seems to delegate to the discretion of the Trustees:
“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.” [Emphasis supplied.] 6
As Trustees, we might well have reached a more generous result. But the narrow scope of our review does not permit us to disturb rational determinations concerning the scope and application of regulations drawn by the Trustees pursuant to discretionary powers granted them by the trust instrument.
“It is a settled principle that trustees having the power to exercise discretion will not be interfered with so long as they are acting bona fide. To do so would be to substitute the discretion of the court for that of the trustee.” 7
The Trustees are at least as well' qualified as the courts to decide such questions.8 I would therefore affirm.
. My brethren say we need not consider the second denial because it “did not appear in the administrative record before the District Court.” It is not clear how the second denial was any less a part of the “administrative record” than the first one . on which the majority does rule. Moreover, since the District Court did not rule on the first denial, and since the Trustees have not relied on it throughout this litigation, it appears that the second denial'is the only one really in issue.
. The letter was from the Director of the Fund who “is empowered to do all things, to perform all necessary acts, and to require the submission of evidence in order to effectuate the purposes of [Resolution 10].
. The District Court found that “there is no evidence that the decision was made in-bad faith or in an arbitrary or capricious manner.”
. Whether unsuccessful efforts to find employment constitute employment for purposes of the Trustees’ various regulations is not a new question in this general area. See Szuch v. Lewis, 193 F.Supp. 831 (D.D.C.1960).
. This is the agreement establishing the United Mine Workers Welfare and Retirement Fund of 1950 involved in the instant case.
. Appellant makes no claim that the Trustees have acted contrary to the purposes of the Fund, the Labor-Management Relations Act, or other applicable law.
. Shelton v. Bang, 229 U.S. 90, 94-95, 33 S.Ct. 686, 687, 57 L.Ed. 1086 (1913). See also 2 Scott on Trusts 1374-1395 (1956). Of. Annot., Rights and liabilities as beUoeen employer and employee with respect to general pension or retirement plan, 42 A.L.R.2d 461 (1955).
. A reviewing court necessarily views such issues in a vacuum, whereas the Trustees consider them against a background of practical considerations and facts not available to the court. For example, the trust fund is by the terms of the Agreement subject to payments for several specified purposes other than pensions, “as agreed upon from time to time by the Trustees.” The Trustees must therefore consider the allocation of available monies to the various purposes which they have chosen to promote. If it appears that one purpose is threatening to draw a disproportionate share of the fund, the Trustees may consider interpreting the eligibility requirements narrowly in order to balance the distribution of benefits. In this case, moreover, they may have considered such factors as the number of people in Danti’s position and the relative difficulty of establishing when a worker stops seeking work as compared to when he stops working. Our inability to weigh such considerations militates against substituting our own interpretation of eligibility requirements for that of the Trustees.