concurring in part and concurring in the judgment in part.
Appellants in No. 74-1316, the Operators, challenge as unconstitutional the retroactive obligations imposed on them by the Federal Coal Mine Health and Safety Act of 1969 (Act), 83 Stat. 792, as amended by the Black Lung Benefits Act of 1972, 86 Stat. 150, 30 TJ. S. C. § 901 et seq. (1970 ed. and Supp. IV). The Court rejects their contention in Part IV of its opinion. I concur in the judgment as to Part IV, and concur in other portions of the opinion not inconsistent with the views herein expressed.
I
Coal miner’s pneumoconiosis was not recognized in the United States until the 1950’s, and there was no federal *39legislation providing benefits to its victims until the enactment of this statute in 1969. In Title IV of the Act, Congress significantly redefined the respective rights and obligations of miners and their employers in regard to this disease by establishing a benefits scheme to compensate victims of pneumoconiosis.1 Under Title IV miners who filed claims before July 1, 1973, are to collect benefits from the Federal Government, §§411-414, 30 U. S. C. §§ 921-924 (1970 ed. and Supp. IV).2 Miners filing claims after June 30, 1973, are to collect benefits-until 1981, see ante, at 26 n. 24, from their individual employers. §§ 415, 421-431, 30 U. S. C. §§ 925, 931-941 (1970 ed. and Supp. IV).3 Under the statute, the class of claimants to which individual employers are liable includes both (i) miners employed at the time of or after enactment and (ii) miners no longer employed in the industry at the time of enactment (former miners).
The unprecedented feature of the Act is that miners may be eligible to receive benefits from a particular coal-mining concern even if the miner was no longer employed in the industry at the time of enactment. The *40Department of Labor already has made initial determinations of liability against one of the Operators and in favor of claimants whose employment terminated decades ago.4
II
The Operators do not challenge their liability to miners employed at the time of or after enactment, a liability which accords with familiar principles of workmen’s compensation.5 They contend, however, that a statutory liability to former miners has been imposed in violation of the Fifth Amendment guarantee against arbitrary, irrational, or discriminatory legislation, see, e. g., Richardson v. Belcher, 404 U. S. 78, 81 (1971), as there *41is no rational justification for imposing liability to former miners upon individual mine owners.
The Court recognizes that its evaluation of the rationality of the employers’ challenged liability must take into account the retroactive nature of the liability:
“The retrospective aspects of legislation, as well as the prospective aspects, must meet the test of due process, and the justifications for the latter may not suffice for the former. Thus, in this case the justification for the retrospective imposition of liability must take into account the possibilities that the Operators may not have known of the danger of their employees’ contracting pneumoconiosis, and that even if they did know of the danger their conduct may have been taken in reliance upon the current state of the law . . . .” Ante, at 17.
The Court then acknowledges that the Act would not be justified “on any theory of deterrence ... or blameworthiness.” Ante, at 17-18. It nonetheless sustains the provision for retroactive liability, reasoning as follows:
“We find . . . that the imposition of liability for the effects of disabilities bred in the past is justified as a rational measure to spread the costs of the employees’ disabilities to those who have profited from the fruits of their labor — the operators and the coal consumers.” Ante, at 18.
“We are unwilling to assess the wisdom of Congress’ chosen scheme by examining the degree to which the 'cost-savings’ enjoyed by operators in the pre-enactment period produced 'excess’ profits, or the degree to which the retrospective liability imposed on the early operators can now be passed on to the consumer. It is enough to say that the Act approaches the problem of cost-spreading rationally Ante, at 18-19.
*42In my view whether the retroactive liability is constitutional is a considerably closer question than the Court’s treatment suggests. The rationality of retrospective liability as a cost-spreading device is highly questionable.
If coal-mining concerns actually enjoyed “excess” profits in the pre-enactment period by virtue of their nonliability for pneumoconiosis, and if such profits could be quantified in some discernible way, Congress rationally could impose retrospective liability for the benefit of the miners concerned. But, in this context, the term “excess profits” must mean profits over and above those that operators would have made in years and decades past if they had set aside from current operations funds sufficient to provide compensation, although under no obligation to do so. It is unlikely that such profits existed. The coal industry is highly competitive and prices normally are determined by market forces. One therefore would expect that, had a compensation increment been added to operating costs, the operators over the long term simply would have passed most of it on to consumers, thereby leaving their profitability relatively unaffected. In short, the talk of “excess profits” in any realistic sense is wholly speculative.
Nor can I accept without serious question the Court’s view that the costs now imposed by the Act may be passed on to consumers. Firms burdened with retroactive payments must meet that expense from current production and current sales in a market where prices must be competitive with the prices of firms not so burdened. One ordinarily would expect that if burdened firms are to meet both competitive prices and their retroactive obligations, their profits necessarily will be less than those of their competitors. Thus, the burdened firms in all likelihood will have to bear the costs of the *43retroactive liability rather than pass those costs on to consumers. And they must bear such costs quite without regard to whether “excess profits” may have been made in some earlier years.6
In some industries conditions might be such that the cost of retroactively imposed benefits could be spread to consumers. It seems most unlikely, however, that the coal industry is such an industry. A notable fact about coal mining is that the industry currently employs only about 150,000 persons, whereas in 1939 it employed nearly 450,000. Brief for Operators 24. The reduced scale of employment in the coal industry, combined with the liability to former miners and their survivors, means that retroactive obligations almost certainly will be disproportionate to the scale of current operations.7 Moreover, it is unlikely that liability to former miners will be distributed randomly across the industry, as it is dictated by historical patterns that may be wholly unrelated to the present contours of the industry. Two examples are illustrative: (i) Some coal-mining concerns have been in the mining business for decades, while some competitors have commenced operation more recently. The exposure of the former group to claims of employees long separated from active employment is likely to be significantly *44greater than that of their competitors, (ii) Some companies engaged in coal mining in years past on a much larger scale and with many more employees than currently. This is not an unusual situation in a “depleting asset” industry, where smaller companies often lack the resources with which to continue the acquisition and development of new properties. Stronger competitors, on the other hand, may have operated on a constant or an increasingly large scale.8 In each case the competitively disadvantaged companies may be unable to spread a substantial portion of their costs to consumers. In view of these considerations it is unrealistic to think that the Act will spread costs to “the operators and the coal consumers,” ante, at 18, and thus I question the Court’s conclusion that the Act is rational in imposing retroactive liability.
Ill
Despite the foregoing, I must concur in the judgment on the record before us. Congress had broad discretion in formulating a statute to deal with the serious problem of pneumoconiosis affecting former miners. E. g., Richardson v. Belcher, 404 U. S. 78 (1971); cf. Williamson v. Lee Optical Co., 348 U. S. 483 (1955). Nor does the Constitution require that legislation on economic matters be compatible with sound economics or even with normal fairness. As a result, economic and remedial social enactments carry a strong presumption of constitutionality, e. g., United States v. Carolene Products Co., 304 U. S. 144, 148 (1938), and the Operators had the heavy burden of showing the Act to be unconstitutional.
*45The constitutionality of the retrospective liability in question here ultimately turns on the sophisticated questions of economic fact suggested above, and these facts are likely to vary widely among the Operators.9 In this case, however, decided on the cross-motions for summary judgment, the Operators have failed to make any factual showings that support their sweeping assertions of irrationality. Although I find these assertions strongly suggestive that Congress has acted irrationally hi pursuing a legitimate end, I am not satisfied that they are sufficient — in the absence of appropriate factual support — to override the presumption of constitutionality. Accordingly, I agree that the federal parties were entitled to summary judgment on this record.
Title II of the Act prescribes the maintenance of less hazardous mine conditions in the future. § 201 et seq., 30 U. S. C. § 841 et seq.
As does the Court, I simplify by not distinguishing between claims by employees and claims by their survivors. See ante, at 15 n. 13.
Claims filed between July 1, 1973, and December 31, 1973, were to be paid by the Federal Government until December 31, 1973, after which they became the responsibility of individual mining concerns. § 415, 30 U. S. C. § 925 (1970 ed., Supp. IV). Liability on the part of individual mining concerns arises only if the claimant does not have recourse to an applicable state workmen’s compensation program approved by the Secretary of Labor, §§ 421-422, 30 U. S. C. §§931-932 (1970 ed. and Supp. IV), but no such state programs have been approved. See ante, at 8-9.
Favorable initial determinations have been made for claimants who left mine work in 1923, 1927, 1931, 1932, 1937, 1943, 1946, and 1948. Brief for Operators 30 n. 1. These determinations rebut the federal parties’ suggestion that in combination the initial period of federal liability and the statute of limitations specified in §422 (f)(1), 30 U. S. C. §932 (f)(1) (1970 ed., Supp. IV), will prevent employer liability to miners who left the industry before passage of the Act. See ante, at 16 n. 14.
Congress apparently recognized that the employers burdened by retroactive liability were not blameworthy. Senator Javits, who played a significant role in the development of individual-employer liability, see Brief for Operators 34, thought that the “blame” for past neglect must be shared by “all of us,” including “the industry, the medical profession, and the Government — particularly the Public Health Service.” House Committee on Education and Labor, 91st Cong., 2d Sess., Legislative History/Federal Coal Mine Health and Safety Act 338 (Committee Print 1970), 115 Cong. Rec. 27627 (1969) (floor remarks).
The retroactive nature of the liability makes deterrence an insufficient justification. In their prospective application, it is rational for Title IV and other workmen’s compensation schemes to disadvantage competitively employers who take less effective precautions to protect their employees. But only prospective liability creates an incentive for occupational safety measures.
It is, of course, impossible to spread the cost to “coal consumers” who "profited from the fruits of [former employees’] labor.” Ante, at 18. A coal-mining concern cannot retroactive!}’ increase its prices to the former customers who benefited from the pre-1969 labors of former miners. The only consumers, therefore, who could bear these burdens are those who purchase coal currently. But in a free market such customers cannot be expected to pay a reparation add-on for coal produced by disadvantaged coal companies when the same product is readily obtainable from others at a lower price.
Indeed, the number of former miners and survivors whom an individual employer is obliged to compensate could be larger than the employer’s present work force.
In addition, the incidence of liability to former miners may be skewed artificially by the regulation imposing liability upon the company which last employed the claimant without regard to previous employment with other companies. 20 CFR § 725.311 (1975). The validity of this regulation remains to be considered. See ante, at 14.
1 would not foreclose the possibility that a particular coal-mining concern, in a proper case, may be able to show that the impact of the Act on its operations is irrational. Cf. ante, at 26-27.