Opinion for the Court filed by Circuit Judge STEPHEN F. WILLIAMS.
Concurring opinion filed by Circuit Judge SENTELLE.
STEPHEN F. WILLIAMS, Circuit Judge:Under the Coal Industry Retiree Health Benefit Act of 1992 (the “Coal Act” or “Act”), 26 U.S.C. §§ 9701-9722 (1994), the duty of paying premiums for the health benefits of certain retired miners falls on the “last signatory operator.” Id. § 9711(a). For the six miners whose benefits are involved here, it is undisputed that Toney’s Branch Coal Company was that operator. But Toney’s Branch is bankrupt. The Act also imposes the duty on any “successor in interest” of the last signatory operator. Id. § 9711(g)(1). Defendant firms Augusta Processing and Williams Mountain never employed any of the six miners, but right after the withdrawal of Toney’s Branch they successively operated Shumate Eagle mine (where Toney’s Branch had employed the six miners), using other miners who had worked at Shumate Eagle for Toney’s Branch, and equipment previously used by Toney’s Branch at the mine. The sole issue before us is whether Augusta and Williams Mountain can on that account be held liable as “successors in interest” of Toney’s Branch.
From 1991 until September 1994 To-ney’s Branch, a “contract mining” firm, mined coal from Shumate Eagle under contract with the mine’s owner. In September 1994 the mine owner terminated the contract with Toney’s Branch and sold the mine. The new owner contracted with Augusta to operate the mine, which it did until October 1995. Augusta used equipment that it had purchased, in an arm’s length transaction, from an affiliate of To-*821ney’s Branch. In October 1995 Williams Mountain bought the mining equipment from Augusta and took up the mining operation. Neither Augusta nor Williams Mountain ever held an ownership interest in Toney’s Branch, or vice versa. Meanwhile, Toney’s Branch continued mining operations elsewhere, until its demise in bankruptcy.
Plaintiffs are trustees of the 1992 United Mine Workers of America (“UMWA”) Benefit Plan (“1992 Plan”). The Plan was established under the Act, as part of Congress’s response to the failure of certain coal companies to pay the health benefits they promised their miners. Under successive National Bituminous Coal Wage Agreements (“NBCWAs”) between the coal operators and the UMWA, companies had agreed to pay benefits not only for their workers but also for workers whose employers had failed- to meet their obligations under the agreement, so-called orphaned workers. R.G. Johnson Co. v. Apfel, 172 F.3d 890, 892 (D.C.Cir.1999). A considerable number of operators responded by withdrawing from the Agreement, either to continue mining with nonunion employees or to leave the coal business altogether. See Eastern Enters. v. Apfel, 524 U.S. 498, 511, 118 S.Ct. 2131, 141 L.Ed.2d 451 (1998). The result was a spiral of increasing obligations for the remaining signatories, and increasing withdrawal. Id. In response, Congress sought to assign health care liability in a form that would be free from such unraveling. Id. at 513-14, 118 S.Ct. 2131.
The plaintiff trustees are obligated to provide benefits for retirees who are entitled to benefits under § 9711 (including the six involved here) but who are not receiving them. 26 U.S.C. § 9712(b)(2)(B). If they cannot compel payment by the last signatory operator, a related person, or a “successor in interest,” they can adjust the premiums they charge employers obliged to contribute to the 1992 Plan. Id. § 9712(d)(2)(B). Thus there is no chance of the miners being denied their benefits. The only issue is whether the expenses will be borne by defendants or by the broad class of coal operators obliged to fund the 1992 Plan. The trustees contend that defendants Augusta and Williams Mountain are “successors in interest” within the meaning of § 9711(g)(1) and therefore responsible for the charges. The district court disagreed and granted summary judgment for defendants. We affirm.
The trustees urge a broad definition of successors in interest, namely the “substantial continuity of operations test.” This is a multi-factor inquiry that examines, among other things, the ability of the predecessor to provide relief; whether the new employer had notice of potential liability; whether he uses the same plant, equipment and workforce; and whether he produces the same product. See, e.g., Secretary of Labor v. Mullins, 888 F.2d 1448, 1453-54 (D.C.Cir.1989). Under this standard, the companies may well be successors in interest to Toney’s Branch: Toney’s Branch is now bankrupt, the Act is familiar to all coal operators, and the companies seamlessly took over operations at Shumate Eagle.
Against this the companies urge narrower definitions, drawn both from general corporate law and from federal tax law (noting that the Act is in fact embedded in Title 26, the Internal Revenue Code (“I.R.C.”)). Black’s Law Dictionary (6th ed.1990), for example, provides the standard corporate law definition:
In order to be a “successor in interest”, a party must continue to retain the same rights as original owner without change in ownership and there must be change *822in form only and not in substance, and transferee is not a “successor in interest.” ... In case of corporations, the term ordinarily indicates statutory succession as, for instance, when corporation changes its name but retains same property.
Id. at 1283-84 (citations omitted). In the alternative, the companies suggest a definition from the I.R.C. that shares with the corporate law definition the element of commingled ownership. See 26 CFR § 1.1503 — 2A(c)(3)(vii)(B); 26 U.S.C. § 381. Under both of these definitions the “successor in interest” is a successor to the wealth of the predecessor, typically through a corporate reorganization. A party simply acquiring property of a firm in an arm’s length transaction, and taking up its business activity, does not become the selling firm’s “successor in interest.” Under both definitions the companies are plainly not successors in interest of To-ney’s Branch, and we need not here wrestle with which of them is to be preferred in the event of a clash.
Because both sides assume that federal law controls the meaning of “successor in interest,” we do the same. See generally Atchison Topeka & Santa Fe Ry. v. Brown & Bryant, Inc., 159 F.3d 358, 362-64 (9th Cir.1998).
At the outset the trustees’ proposed reading of § 9711(g)(1) encounters difficulty from the adjacent statutory language. While § 9711(g)(1) mandates that “successors in interest” share liability with last signatory operators, § 9711(g)(2) permits “successors” to assume by contract liability for health benefits owed to retirees. The natural reading is that Congress intended “successors” in subsection (g)(2) to include a broad class of persons, e.g., firms that take over mining operations from others, and are not liable as a matter of law, but assume liability by contract with the seller to suit the mutual convenience and risk-allocation preferences of the contracting firms. If § 9711(g)(1) imposed liability by law on virtually all potential candidates for the (g)(2) transaction, the latter would, for the most part, be surplusage. See Holland v. New Em Coal Co., 179 F.3d 397, 403 (6th Cir.1999).
The trustees respond that, because the section heading for § 9711(g)(1) is “Successor,” Congress intended the terms “successor” and “successor in interest” to be used interchangeably. For them the only role of § 9711(g)(2), as against subsection (g)(1), is to allow successors to contract for primary responsibility. But, quite apart from the customary reluctance to give great weight to statutory headings, see, e.g., Bhd. of R.R. Trainmen v. Baltimore & Ohio R.R. Co., 331 U.S. 519, 528-29, 67 S.Ct. 1387, 91 L.Ed. 1646 (1947), it seems very odd to use a heading, which normally is a kind of shorthand, to justify stripping the actual text of two words, “in interest,” that were obviously included deliberately.
This conclusion accords with the structure of the Act. Section 9711 specifies two groups that share liability with last signatory operators: related parties and successors in interest. Related persons, defined in § 9701(c)(2)(A), encompass members of a controlled group of corporations including the signatory operator in question, a business under common control with the signatory operator, and a person in a partnership or joint venture with the signatory operator in the coal business. A common feature of all such entities is that they share ownership or comparable economic interests with the signatory operator. Understanding successor in interest as embodying the standard corporate concept gives it a closely congruent meaning.
We note that the Internal Revenue Service has promulgated definitions of “sue-*823cessor in interest” for various specific purposes. See, e.g., 26 CFR § 1.1503-2A(c)(3)(vii)(B); id. § 301.6110-2(0; id. § 302.1-l(e). See also In re Leckie Smokeless Coal Co., 99 F.3d 573, 585 n. 14 (4th Cir.1996). Because of the variety of definitions we question whether the term can be said to have received the sort of consistent treatment that led the Supreme Court in Commissioner v. Keystone Consolidated Industries, Inc., 508 U.S. 152, 113 S.Ct. 2006, 124 L.Ed.2d 71 (1993), to infer, for the phrase “sale or exchange,” an intent to incorporate a previously “settled” meaning. Id. at 159, 113 S.Ct. 2006. But we also note that the trustees do not claim that any of the definitions chosen by the IRS in other contexts is broad enough to sweep in the two coal companies here.
In sum, then, the text and structure of § 9711 point powerfully toward the two companies’ position. The trustees, however, brush aside this textual analysis and offer three arguments to support a broad definition of successors in interest. First, they contend that the Act is a remedial statute and therefore should be liberally construed. This is meaningless. All statutes seek to remedy some problem, so the maxim does nothing to identify what statutes should be “liberally construed” (assuming that phrase to have a discrete meaning). E. Bay Mun. Util. Dist. v. U.S. Dep’t of Commerce, 142 F.3d 479, 484 (D.C.Cir.1998); Ober United Travel Agency, Inc. v. U.S. Dep’t of Labor, 135 F.3d 822, 825 (D.C.Cir.1998).
Second, trustees argue that broad successor liability fits Congress’s stated intent to assign the duty of paying premiums “to persons most responsible for plan liabilities.” 26 U.S.C. § 9701 note (Findings and Declaration of Policy) (quoting § 19142 of Pub.L. No. 102-486). For our purposes Congress here selected the last signatory operator, Toney’s Branch, the last firm to receive benefits from the six miners’ labor. After that the Act assigns liability to related persons, § 9711(b), and to successors in interest, § 9711(g)(1). What the trustees fail to explain is why companies such as the two here — whose only link to the six miners is to have started mining operations with equipment bought from Toney’s Branch, after the six retired, at the mine where the six had formerly worked — are in any material respect more “responsible” for plan liabilities for the six than is the broad class of firms funding the 1992 Plan. The defendants’ arm’s length purchase of mining equipment at the Shumate Eagle mine seems to tie them to the six miners no more than would any firm’s purchase of any assets (office equipment, real property, etc.) from Toney’s Branch. The set of operators that would bear the premiums for the six miners’ benefits under the 1992 Plan, however, are all signatories to the 1988 NBCWA, whereby they have promised to fund the benefits of orphan retirees. The Seore-tary op Labor’s Advisory Commission on United Mine Woreers of America Retiree Health Benefits, Coal Commission Report 27 (Nov.1990). The Coal Act merely enforces these promises. 26 U.S.C. § 9712(d).
Even if Congress’s purpose were recast in more general terms — securing health benefits for retired miners, see, e.g., 26 U.S.C. § 9701 note (Findings and Declaration of Policy) — broad successor liability is hardly essential to that goal. The six miners will receive benefits regardless of whether the defendants are billed for them. To address the concern that in the absence of successor liability the scheme set up by the Act might collapse as last signatory operators sold off assets, pocketed the money, and declared bankruptcy, the Act itself expressly denies effect to any transaction of which a “principal purpose *824... is to evade or avoid liability.” 26 U.S.C. § 9722. The bankruptcy laws similarly provide relief against fraudulent transfers. See, e.g., 11 U.S.C. § 548. Nor is it the case that lack of “successor liability would discourage some conduct Congress sought to encourage; this contrasts (for instance) with the Multiemployer Pension Plan Amendments Act (“MPPAA”) of 1980, where courts have been concerned that without broad successor liability firms would be discouraged from joining preexisting multi-employer pension agreements. See Upholsterers’ Int’l Union Pension Fund v. Artistic Furniture of Pontiac, 920 F.2d 1323, 1329 (7th Cir.1990). Here the classes of both beneficiaries and ultimate obligors is substantially fixed. Not only does the Act apply solely to miners who retired by September 30, 1994, 26 U.S.C. § 9712(b)(2), but it legally obligates their employers, if they have signed a 1988 NBCWA, to provide benefits, id. §§ 9712(d), 9701(c)(3).
The trustees’ final argument is that courts have often used the substantial continuity test to determine successor liability in federal statutes (particularly those adopted for the protection of employees), even when those statutes include no language directly supporting liability for successors of any kind. Because statutory interpretation proceeds on the assumption that Congress’s choice of words reflects a familiarity with judicial treatment of comparable language, Traynor v. Turnage, 485 U.S. 535, 545-46, 108 S.Ct. 1372, 99 L.Ed.2d 618 (1988), we cannot say, without some consideration of the cases using substantial continuity, that the trustees’ claim is a priori wrong. In reality, however, courts have adopted that standard only in the presence of certain factors, the most notable of which, at least, is palpably missing here.
Before presenting our core objections to the trustees’ argument, we review, for context, the origins of the substantial continuity test. Under the traditional rule on corporate successorship liability, a corporation that acquires manufacturing assets from another corporation does not thereby assume the liabilities of the seller. The rule admits four exceptions: (1) when the successor expressly or impliedly assumed those liabilities; (2) when the transaction may be construed a de facto merger; (3) when the successor may be considered a “mere continuation” of the predecessor; and (4) when the transaction was fraudulent. See Mozingo v. Correct Mfg. Corp., 752 F.2d 168, 174 (5th Cir.1985) (citing 15 William Meade Fletcher, Fletcher Cyclopedia of the Law of Private Corporations, § 7122 (Perm, ed.1983)). Most relevant for our purposes is the “mere continuation” exception. Traditionally, this applies when, after the transfer of assets, there is an identity of stock, stockholders, and directors between the purchasing and selling corporations. See, e.g., Weaver v. Nash Int’l, Inc., 730 F.2d 547, 548 (8th Cir.1984). Thus the “mere continuation” exception appears to closely parallel the basic “successor in interest” concept invoked by Augusta and Williams Mountain.
As the Third Circuit has observed, the traditional rule concerning the liability that attaches to asset sales was “designed for the corporate contractual world,” and “protects creditors and dissenting shareholders, and facilitates determination of tax responsibilities, while promoting free alienability of business assets.” Polius v. Clark Equipment Co., 802 F.2d 75, 78 (3rd Cir.1986). But it is also generally applied in cases involving tort plaintiffs, see, e.g., id. at 82-83; Travis v. Harris Corp., 565 F.2d 443, 446 (7th Cir.1977), and the beneficiaries of federal statutes, see, e.g., Atchison Topeka & Santa Fe Ry., 159 F.3d at *825364 (Comprehensive Environmental Response, Compensation and Liability Act (“CERCLA”)), even though such parties may have had no real opportunity to protect their interests by contract with the predecessor corporation. For their protection some courts have stretched the “mere continuation” test into the substantial continuity of operations test advocated by the trustees, see Polius, 802 F.2d at 78 (noting cases); Cyr v. B. Offen & Co., 501 F.2d 1145, 1152-54 (1st Cir.1974). The majority, however, still follow the traditional rule in tort cases, see Polius, 802 F.2d at 80 (products liability); Restatement (THIRD) OF TORTS: PRODUCTS LIABILITY § 12 cmts. a, b (1997), and in cases involving federal statutes such as CERCLA, see Atchison, Topeka & Santa Fe Ry., 159 F.3d at 364.
In the context of federal statutes whose primary beneficiaries are employees, however, it appears that most courts invoke the substantial continuity test. This departure from the traditional rule was sparked by four Supreme Court cases, two involving disputes under the National Labor Relations Act (“NLRA”), Golden State Bottling Co. v. NLRB, 414 U.S. 168, 94 S.Ct. 414, 38 L.Ed.2d 388 (1973); NLRB v. Burns Int’l Security Servs., Inc., 406 U.S. 272, 92 S.Ct. 1571, 32 L.Ed.2d 61 (1972), and two the Labor Management Relations Act (“LMRA”), Howard Johnson Co. v. Detroit Local Joint Executive Bd., Hotel & Rest. Employees & Bartenders Int’l Union, 417 U.S. 249, 94 S.Ct. 2236, 41 L.Ed.2d 46 (1974); John Wiley & Sons, Inc. v. Livingston, 376 U.S. 543, 84 S.Ct. 909, 11 L.Ed.2d 898 (1964). Neither statute mentions successors, let alone successors in interest. Steinbach v. Hubbard, 51 F.3d 843, 845 (9th Cir.1995). Yet, proceeding under principles of equity, the Court in each case addressed the extent to which successors to the originally liable firm’s operations could be lawfully burdened with promises entered or statutory torts committed by their predecessors. The Court weighed congressional interest in the policy promoted by the statute, and the extent to which successor Lability would promote it, against the cost and inequity to the successor of imposing liability. See, e.g., Golden State, 414 U.S. at 184, 94 S.Ct. 414; Burns Int’l, 406 U.S. at 287-88, 92 S.Ct. 1571.
Although the four cases concerned the core labor relations statutes, the reasoning has been used to find broad successor liability under other statutes that govern employees’ rights whether they explicitly address successor liability, Leib v. Georgia-Pacific Corp., 925 F.2d 240, 244-45 (8th Cir.1991) (Vietnam Era Veterans’ Readjustment Assistance Act of 1974 (“VEV-RAA”)); Vanderhoof v. Life Extension Inst., 988 F.Supp. 507, 512-13 (D.N.J.1997) (Family Medical Leave Act) (relying on NLRA and Title VII case law), or not, Wheeler v. Snyder Buick, Inc., 794 F.2d 1228, 1235-36 (7th Cir.1986) (Title VII); Musikiwamba v. ESSI, Inc., 760 F.2d 740, 745-46 (7th Cir.1985) (Civil Rights Act of 1866). In none of these cases, however, did the text and structure of the underlying legislation point firmly against successor liability based on substantial continuity of operations. The four Supreme Court cases that provide authority for these cases, for example, interpreted a pair of statutes that, unlike the statute before us, failed to give guidance on successor liability one way or the other. Moreover, even pursuing this line of cases would leave our conclusion unchanged.
A key factor motivating courts to extend successor liability beyond the textual bounds of a statute is that the victim of the predecessor’s behavior may be left without a remedy unless recourse against the successor is allowed. Musikiwamba, 760 F.2d at 746. (This is, of course, ordinarily *826an aspect of Congress’s intent.) The relief sought under the statutes involved in the Howard Johnson-Golden State line of cases is typically “nonmonetary and can be effective only if directed against the workers’ current employer.” EEOC v. G-K-G, Inc., 39 F.3d 740, 748 (7th Cir.1994) (Age Discrimination in Employment Act (“ADEA”)); see, e.g., Harter Tomato Prods. Co. v. NLRB, 133 F.3d 934, 936-37 (D.C.Cir.1998) (successor’s duty under NLRA to bargain with union for predecessor’s employees); Leib, 925 F.2d at 247 (successor’s duty under VEVRAA to rehire predecessor’s employee); Criswell v. Delta Air Lines, Inc., 868 F.2d 1093, 1094 (9th Cir.1989) (successor’s duty under ADEA to rehire predecessor’s worker and change mandatory retirement policy); Bates v. Pac. Maritime Ass’n, 744 F.2d 705, 710-11 (9th Cir.1984) (successor’s duty to obey Title VII consent decree requiring a certain level of representation of blacks among workforce at a harbor). Even if the remedy sought by the plaintiff in a particular case is simply damages, the possibility that other plaintiffs suing under the same statute may seek injunctive relief supports successor liability under that statute. G-K-G, 39 F.3d at 748. But the Coal Act contemplates no specific performance remedies. 26 U.S.C. § 9711(a); see also id. §§ 9704(a), 9712(d). Because (1) only pure money cases may be brought, (2) the “successor in interest” standard of corporate law allows the beneficiary (or the 1992 Plan trustees) to pursue the wealth of the last signatory operator, and (3) the Coal Act as a whole assures protection for the beneficiary without his incurring the costs and risks of pursuing a departed past employer, there is no warrant whatever for broad successor liability.
Thus we reject the trustees’ claim that § 9711(g)(1) adopts the “substantial continuity of operations” test. As we observed before, the two companies prevail here under either of their candidates — the general corporate definition or one of the special tax definitions, see, e.g., 26 CFR § 1.1503-2A(c)(3)(vii)(B); 26 U.S.C. § 381. Accordingly we may leave to another day the resolution of any differences in detail between these and possibly other candidates.
The judgment of the district court is
Affirmed.