219 N.J. Super. 601 (1987) 530 A.2d 1287

CLARA MORGAN SHACKIL, ALBERT SHACKIL, AND DEANNA MARRERO, P/P/A HER MOTHER AND NEXT FRIEND CLARA MORGAN SHACKIL, PLAINTIFFS-APPELLANTS,
v.
LEDERLE LABORATORIES, A DIVISION OF AMERICAN CYANAMID CO.; AND WYETH LABORATORIES, A DIVISION OF AMERICAN HOME PRODUCTS CORPORATION; WYETH LABORATORIES, INC.; PARKE-DAVIS, A DIVISION OF WARNER-LAMBERT CO.; ELI LILLY AND COMPANY, DEFENDANTS-RESPONDENTS, AND PITTMAN-MOORE AND ITS SUCCESSOR, THE DOW CHEMICAL COMPANY AND LEO FELD, M.D., DEFENDANTS.

Superior Court of New Jersey, Appellate Division.

Argued June 10, 1987. Decided August 12, 1987.

*607 Before Judges DREIER, SHEBELL and STERN.

Jan Schlichtmann, pro hac vice, of the Massachusetts Bar, argued the cause for appellant (Blume, Vasquez, Goldfaden, Berkowitz & Oliveras, attorneys; John M. Blume, of counsel; Michael R. Hugo, on the brief).

J. Peter Coll, Jr., pro hac vice, of the New York Bar, argued the cause for respondent Lederle Laboratories (Morgan, Melhuish, Monaghan, Arvidson, Abrutyn & Lisowski, attorneys; James L. Melhuish, of counsel and on the brief).

Anita Hotchkiss argued the cause for respondent Wyeth Laboratories, Division of American Home Products Corporation, Wyeth Laboratories, Inc. and Parke Davis & Company (Porzio, Bromberg & Newman, attorneys; Ms. Hotchkiss, of counsel and on brief; and Lisa Murtha, on the brief).

John L. McGoldrick argued the cause for respondent Eli Lilly & Company (McCarter & English, attorneys; Mr. McGoldrick, of counsel and on the brief; John F. Brenner, Jerry P. Sattin, Richard A. Bagger and Marna L. Brown, on the brief; Shook, Hardy & Bacon, of counsel).

McDonough, Murray & Korn, attorneys for Leo Feld, M.D. (William S. Mezzomo, on the brief).

Thomas F. Campion argued the cause amicus curiae for Merck & Co., Inc. (Shanley & Fisher, attorneys; Mr. Campion, of counsel and on the brief).

*608 Tompkins, McGuire & Wachenfeld filed a brief amicus curiae for Abbott Laboratories (William B. McGuire, of counsel and on the brief).

Lamb, Hartung, Coughlin, Kretzer & Reinman filed a brief amicus curiae for The Upjohn Company (Edwin A. Hartung, of counsel and on the brief).

The opinion of the court was delivered by DREIER, J.A.D.

Plaintiffs have appealed, by leave granted, from an interlocutory order dismissing their negligence, warranty, misrepresentation, and strict liability action against Lederle Laboratories, Wyeth Laboratories, a Division of American Home Products Corporation, Wyeth Laboratories, Inc., Parke-Davis, and Eli Lilly & Co. By amended complaint plaintiff added Pittman-Moore as a defendant. National Drug Company, an additional manufacturer of the drug in question, was not joined, since plaintiffs contended that as a result of their discovery they found no basis to determine that the drug actually administered was manufactured by National Drug Company.^[1]

The claims in this case arose out of an administration of the pertussis (whooping cough) antigen component of a pharmaceutical product known as the diphtheria, pertussis and tetanus toxoid (DPT) vaccine. The DPT vaccine is not a formularized synthetic chemical substance, but rather a licensed prescription biological product subject to the provisions of the Federal Food, Drug & Cosmetic Act, 21 U.S.C.A. § 301 et seq. (1972), and the Public Health Service Act, 42 U.S.C.A. § 262 et seq. (1982). Each manufacturer of a DPT vaccine has its own proprietary process for creating the vaccine, protected either by trade secret or patent, and often marketed under trade names. Some of the characteristics of the biological products may vary with *609 the processes used. Immunization with the vaccine is required by law, N.J.S.A. 26:1A-7, 30:5B-5; N.J.A.C. 8:57-4.10, and the beneficial effect of the vaccine is generally acknowledged. The immunization program has reduced and in some areas virtually eliminated diphtheria, whooping cough and tetanus in young children.

Plaintiffs, however, contend that the product was defective in that it contained toxins which could have been eliminated by the use of the technology existing at the time the infant plaintiff, Deanna Marrero, was inoculated. Further, plaintiffs assert that the inoculations administered by the defendant physician caused Deanna to suffer a seizure disorder, resulting in chronic encephalopathy and severe retardation, and changing an otherwise normal two-year old into a mental incompetent requiring institutionalization.^[2] Deanna's mother first noted the problem immediately following the booster shot, but was told by defendant physician that Deanna's conduct might well be indicative of her entering the "terrible twos." Thereafter, as Deanna's condition steadily worsened, her mother claims she had no indication of the relationship between the DPT injections and her daughter's condition. She testified in a deposition that in June 1984 she

... read an article that was in the Boston paper about the side effects of the D.P.T., well, mainly of the pertussis, and that it could cause brain damage and when I read it, it was like a light went off in my head and I finally saw something in black and white that I had suspected for many years but was never — no one ever really acknowledged that that was what it was.

She also described the regression in her daughter's development:

*610 Her eyes were crossing, her speech regressed and she would not get up when lying down or sitting. She was no longer interested at looking at pictures in a book. She began negative self-stimulation behavior such as compulsively twisting her hands. She began seizure activity. At approximately 4 years she began to grit her teeth, hold her breath and contort her face. She did not reach many of her developmental milestones. At six years she began episodes of hysterical uncontrollable crying. Today as a result of the inoculations, Deanna is severely retarded and requires constant care.

This suit was filed April 12, 1985 when Deanna was 14 years old, nearly 13 years after the administration of the last injection. By that time records were unavailable to the parties as to the identity of the manufacturer of the particular DPT vaccine used by the treating physician. Plaintiffs, therefore, instituted this action against all manufacturers whose products had been used by the treating physician during the period in question, asserting a theory of collective responsibility.^[3]

Although the defendant manufacturers have raised various other defenses, treated later in this opinion, the trial judge correctly determined that he was bound by Namm v. Charles E. Frosst & Co., 178 N.J. Super. 19 (App.Div. 1981), which rejected all theories of collective responsibility.^[4] While in no way impugning the decision of the trial judge who was bound *611 by existing appellate authority to dismiss the complaint against the drug manufacturers, we now reconsider the Namm holding. Defendants have raised several bases upon which they claim the DPT cases differ from those in which any theory of collective responsibility has been applied. While they disagree that any such theory should apply, they contend that the theories are limited in application to generic or truly fungible products and to factual settings that differ from the one before this court. We will briefly treat these arguments before approaching the central issue of whether New Jersey should adopt one or more of the recognized theories or some modification thereof. These arguments, however, point out some flaws in the recognized theories of responsibility in non-identification cases, primarily in the failure of these rules to adapt to the specific factual settings of individual cases and to coordinate with other recognized tort principles.

I. Preliminary Considerations.

A.

First, defendants claim that they are without fault in plaintiffs being denied access to information concerning the identity of the manufacturer. This was not a case where there is a recognized long latency period and pharmaceutical records were destroyed in the interim, such as in the DES cases. See, e.g., Sindell v. Abbott Laboratories, 26 Cal.3d 588, 163 Cal. Rptr. 132, 607 P.2d 924, cert. den. 449 U.S. 912, 101 S.Ct. 285, 66 L.Ed.2d 140 (1980); and the other DES cases cited infra. The Federal Food & Drug Administration (FDA) has formulated rules and regulations which encompass the licensing, testing, production, distribution, review and approval of each DPT vaccine. One such requirement is that each manufacturer must make a written record of the name and address of each person to whom a specific lot of the vaccine has been distributed and that record must be retained for no less than five years after the date of manufacture or six months after the expiration date for that product, whichever is later. 42 C.F.R. § 73.502(b)(1) (1971); 21 C.F.R. § 600.12(a)(b)(1) (1986). Likewise, although *612 the doctor and his drug distributor had retained their records for several years, they then destroyed them.

Defendants, however, misperceive the element of superior access to information discussed in some cases. It is not an element of a cause of action; rather, it is a consideration to be weighed in a balancing process to determine whether some form of collective responsibility should fairly be applied. In the case before us, there is no question that the applicable statute of limitations has not run since this action was filed during the infant plaintiff's minority. N.J.S.A. 2A:14-21. Even if there had been no tolling statute, the cause of action may well have been preserved under New Jersey's discovery rule. Vispisiano v. Ashland Chemical Company, 107 N.J. 416, 437 (1987); Lopez v. Swyer, 62 N.J. 267 (1973); cf. Hadden v. Eli Lilly & Co., 208 N.J. Super. 716 (App.Div. 1986), certif. den. 104 N.J. 441 (1986).

While the cause of action itself is not barred, a court might nevertheless consider that the imposition of a theory of collective responsibility should be governed by considerations of laches, i.e., an unexplained or inexcusable delay in enforcing a known right resulting in prejudice to the other party. See Gladden v. Public Employees' Retirement System Trustee Board, 171 N.J. Super. 363, 370-371 (App.Div. 1979). But, based upon the limited information before us, it appears that plaintiffs here are without fault in making a late, but not time-barred, claim. There was no showing that the child's mother knew or should have known that encephalitis was a recognized side effect of the DPT vaccine and that she consequently should have made the connection between the vaccination and her daughter's condition, especially since she was reassured of the lack of connection by the treating physician. Cf. Vispisiano v. Ashland Chemical Company, supra; Lopez v. Swyer, supra. If there is a serious factual dispute as to this point and a trial judge determines that it would be equitably inappropriate to apply a doctrine of collective responsibility under particular facts, the issue should be resolved on remand. Abel v. Eli Lilly & Co., 418 Mich. 311, 343 N.W.2d 164, 173 *613 (1984), cert. den. sub nom. E.R. Squibb & Sons, Inc. v. Abel, 469 U.S. 833, 105 S.Ct. 123, 83 L.Ed.2d 65 (1984). Such a future resolution does not affect the underlying ruling here on appeal that no cause of action exists under any theory of collective responsibility.

This "laches" consideration does not directly meet defendants' allegation that they are not in a superior position to plaintiff to determine which manufacturer's product affected the infant plaintiff, and that their inability to identify which of them was the manufacturer was due to plaintiffs' failure to assert their claim promptly. Although the federal requirements mandate only a five year retention of drug records, defendants knew that their drugs were being administered to young children and that a devastating and disabling illness might be caused in a small but acknowledged percentage of cases. Recognizing that statutes of limitation have infancy and incompetency tolling provisions, the drug companies could have chosen to retain their records for a longer period of time, thus obviating the identification problem now before the court. Plaintiffs had no similar ability to resolve the identification problem. This issue, therefore, presents no bar to our determining whether a collective responsibility doctrine is viable in New Jersey.

B.

Defendants next claim that their products are not generic or fungible, and, therefore, all doctrines of collective responsibility are inapplicable. Even acknowledging that defendants' products are protected by patents or trade secrets and differ from each other, we must focus upon the fact that each of the products subjected the user to a similar recognized danger of encephalitis. It makes little difference to a consumer what the internal biological or chemical nature of a product may be if it might cause a specific common health problem. Since there is then no way to determine the particular manufacturer's product *614 on the basis of the result for the purpose of applying a doctrine of collective responsibility, the products must be considered virtually identical. The differences in their composition, except as such differences might affect the frequency of the adverse result, must be considered as irrelevant as the color of the label on the package.

C.

There are, however, differences alleged by defendants in the products insofar as the frequency of encephalopathic disorder caused by each defendant's vaccine. In particular, Eli Lilly asserts that its DPT product, Tri-Solgen, was fundamentally different from that marketed by the other manufacturers.^[5] Each manufacturer, however, has records concerning the incidence of chronic encephalitis resulting from the administration of its vaccine. We see no impediment to a defendant introducing such evidence insofar as it affects the probability that its vaccine caused the injury. Since, as noted infra, we have directed the trial judge to proceed applying a risk-modified market share analysis, with several, as opposed to joint and several, responsibility, proof by a defendant of the reduced incidence of encephalitis would result in a proportional lowering *615 of the percentage responsibility for such defendant. This factor, therefore, is relevant, but not exculpating, so long as there is a discernible and quantifiable incidence of the disease from the administration of the product.^[6]

D.

Defendants also assert that their vaccines are not a suitable subject for collective responsibility since the toxicity which could cause encephalitis varies not only from manufacturer but also from batch to batch. Were this a true "bad batch" case, i.e., a claim concerning a product which ordinarily created no problems but due to some error in manufacture became toxic, identification of the particular defendant would be mandatory. See, e.g., Centrone v. C. Schmidt & Sons, Inc., 114 Misc.2d 840, 452 N.Y.S.2d 299, 304 (Sup.Ct. 1982); Sheffield v. Eli Lilly & Co., 144 Cal. App.3d 583, 192 Cal. Rptr. 870 (Ct.App. 1983). If defendants advance this "bad batch" defense, it would be incumbent upon plaintiff to prove which manufacturer put the defective product on the market. Plaintiffs, however, have asserted that the product was defective in that it could have been supplied under then-existing technology in a form untainted by the toxins which caused the encephalitis.

E.

Defendants next urge that the product was so inherently beneficial and the incidence of problems was so low that the public interest demands a freedom from liability.^[7] The record is replete with defendants' praise of the DPT vaccine and the devastating consequences to the contrary if these vaccines are to *616 be removed from the market. We recognize the benefits of defendants' products. Indeed, in parallel situations where potential liability might have removed similar pharmaceutical products from the market place, Congress has recognized the problem by enacting immunity legislation. See e.g., National Swine Flu Immunization Program of 1976, Pub.L. No. 94-380, 90 Stat. 1113 (1976). Also compare recently enacted New Jersey legislation, N.J.S.A. 2A:58C-4, absolving a manufacturer from liability for harm caused by a failure to warn.

[i]f the warning or instruction given in connection with a drug ... has been approved or prescribed by the federal Food and Drug Administration under the `Federal Food, Drug and Cosmetic Act, 52 Stat. 1040, 21 U.S.C. § 301 et seq. ...,

in which case there is a rebuttable presumption "that the warning or instruction is adequate." In short, if it is legislatively determined that the social utility of producing the product, even if defective, far outweighs the risk to the few individuals who may be harmed, either Congress or the State Legislature may grant an appropriate immunity. But no such immunity now exists.

Compliance with even existing federal regulations might well, upon proper proof, be found to bar plaintiffs' claims insofar as they are based upon a failure to warn. Cipollone v. Liggett Group, Inc., 789 F.2d 181 (3d Cir.1986), cert. den. ___ U.S. ___, 107 S.Ct. 907, 93 L.Ed.2d 857 (1987) (involving adequacy of cigarette labelling and advertising); McQuaid v. Burlington County Memorial Hospital, 212 N.J. Super. 472, 475-476 (App. Div. 1986) (raising the question whether FDA action dictating the warning to be given "does not indeed provide [the drug manufacturer] with an absolute defense"); and compare Feldman v. Lederle Laboratories Inc., 97 N.J. 429, 446 (1984), which left open the issue whether compliance with FDA warnings absolved defendants from strict liability and which found the record in that case insufficient.

to analyze fully the risk and benefits of prescription drugs and to conclude that drug manufacturers should be immune from strict liability for failure to produce drugs that are safe, suitable and fit for their intended purposes.

*617 Unlike the complete product immunity in the cases involving swine flu vaccine, section 4 of the New Jersey statute^[8] and the cited cases all involve warning immunities, and thus are limited to failure to warn cases. This, however, is a design defect case, and the warning preemption cases are inapposite. Yet there are also design defect preemption considerations, not yet treated in New Jersey law, but cogently explored in the DPT cases of Toner v. Lederle Laboratories, 112 Idaho 328, 343 n. 12, 732 P.2d 297, 311 n. 12 (1987), and Hurley v. Lederle Lab., Div. of Am. Cyanamid, 651 F. Supp. 993, 1003-1006 (E.D.Tex. 1986). We express no opinion as to this issue which also should be fully explored by the trial judge on remand.

A related question involves the defense to a product claim involving a pharmaceutical product envisioned by comment k to Restatement, Torts 2d, § 402A at 353-354. The comment states:

There are some products which, in the present state of human knowledge, are quite incapable of being made safe for their intended and ordinary use. These are especially common in the field of drugs.

The comment then gives as an example the Pasteur treatment of rabies and notes:

The same is true of many other drugs, vaccines and the like, many of which for this very reason cannot legally be sold except to physicians, or under the prescription of a physician.... The seller of such products, again with the qualification that they are properly prepared and marketed and proper warning is given, where the situation calls for it, is not to be held to strict liability for unfortunate consequences attending their use, merely because he has undertaken *618 to supply the public with an apparently useful and desirable product, attended with a known but apparently reasonable risk.

See Calabrese v. Trenton State College, 162 N.J. Super. 145 (App.Div. 1978), aff'd on other grounds 82 N.J. 321 (1980) (affirming summary judgment for manufacturer, distributor and retailer of drug, and classifying anti-rabies vaccine as an "unavoidably unsafe" product as defined by comment k of Restatement, Torts 2d, § 402A); Brody v. Overlook Hospital, 127 N.J. Super. 331 (App.Div. 1974), aff'd 66 N.J. 448 (1975) (finding blood, contaminated by hepatitis antibodies not then discoverable, as falling within the "unavoidably unsafe" product definition of comment k of § 402A). But we note from the discussion in Feldman v. Lederle Laboratories, supra, of comment k to Restatement, Torts 2d, § 402A, that New Jersey does not read comment k as granting immunity from responsibility upon all makers of prescription drugs.

Comment k immunizes from strict liability the manufacturers of some products, including certain drugs, that are unavoidably unsafe. However, we see no reason to hold as a matter of law and policy that all prescription drugs that are unsafe are unavoidably so. Drugs, like any other products, may contain defects that could have been avoided by better manufacturing or design. Whether a drug is unavoidably unsafe should be decided on a case-by-case basis; we perceive no justification for giving all prescription drug manufacturers a blanket immunity from strict liability manufacturing and design defect claims under comment k. [97 N.J. at 447].

Plaintiffs have here assumed the burden of showing that all of the DPT vaccines manufactured by all of the defendants were in fact defective, in that by defendants' applying the existing scientific knowledge and technology available at the time of manufacture and distribution, the contaminating toxins need not have been present in the serum. The products were not, they claim, "unavoidably" unsafe. But defendants have the burden of proving their affirmative defense under comment k. See Toner v. Lederle Laboratories, supra, 112 Idaho at 339-340, 732 P.2d at 308-309 (applying New Jersey and California authorities). This factual issue in a DPT case, if a viable cause of action exists under one or more of the theories of collective responsibility, must be resolved at trial.

*619 F.

Next, defendants allege that plaintiffs have not eliminated other possible causes for Deanna's tragic condition. This also was a factual issue which properly was not reached by the trial judge, since he determined the matter on the basis of the lack of a viable legal theory upon which liability could have been imposed. This, as well as the other fact-sensitive matters urged by defendants but not passed upon by the Law Division, are not before us on this interlocutory appeal.

Many, if not all, of these issues would have required time-consuming and expensive proof on the part of both plaintiffs and defendants, and the trial judge was correct in disposing of this case on the basis of the underlying legal issue where there was controlling appellate precedent. Since many of the factual issues also would have been raised with respect to the remaining defendant, the treating physician who prescribed the vaccine, we granted leave to appeal this interlocutory determination. Also, this case provides a vehicle for reviewing the decision in Namm, unfettered by the factual analysis which would have been required if the trial judge had disposed of each of these issues. We recognize that in similar situations the Supreme Court has remanded matters to the Law Division for expansion of the factual records. See Wolfsbruck v. Dow Chemical Co., 101 N.J. 252 (1985), and Salomon v. Eli Lilly & Co., 98 N.J. 58, 59-60 (1984). Although the Salomon case, after expansion of the record, apparently is to be reheard by the Supreme Court at some future time, it appears unfair to require both plaintiffs and defendants in this case to expend tens or even hundreds of thousands of dollars in trial costs without knowing whether a viable theory of collective responsibility exists in New Jersey.

II. Theories of Collective Responsibility.

A.

This court in Namm, citing Gray v. U.S., 445 F. Supp. 337, 338 (S.D.Tex. 1978), and textual sources, stated

*620 `it is a fundamental principle of products liability law that a plaintiff must prove, as an essential element of his case, that the defendant manufacturer actually made the particular product which caused the injury.' [178 N.J. Super. at 27].

The Namm court also cited Scanlon v. General Motors Corp., 65 N.J. 582, 590 (1974) for this principle. An examination of Scanlon, however, shows that the Supreme Court focused upon the condition of the product when it left the manufacturer's hands, as the identity of the manufacturer was not in dispute. We find no Supreme Court authority in New Jersey imposing an absolute requirement of identification of a manufacturer. In the usual case it is only "one who sells [i.e., a manufacturer, distributor or a retailer] any product in a defective condition" who is subject to strict liability under Restatement, Torts 2d, § 402A, and there is an extensive series of Supreme Court cases adopting this general principle. We disagree, however, with Namm's finding that any Supreme Court case prohibits our holding each of those who sell substantially similar products (the effects of which after the passage of time cannot readily be distingished from one another) collectively as "sellers" within the meaning of § 402A.

The Namm court next determined, and our dissenting colleague agrees, that "traditional concepts and basic principles would of necessity be either distorted or abandoned altogether" if any theory of alternative liability was adopted. 178 N.J. Super. at 34. Further, the court found, quoting a workers' compensation case, that an intermediate appellate court should "adhere to existing laws of the State and in the absence of appropriate amendatory legislation" should defer to the Supreme Court. Ibid. We fully subscribe to this principle where there is Supreme Court precedent or even dictum to the contrary, or where the Legislature has spoken and the matter is thus taken from the purview of the common law. The majority and dissent welcome the Legislature's entrance into this field, demonstrated by the legislation cited above. But we note that the specific problem before us has not been addressed in the new Act.

*621 If an intermediate appellate or trial court must decide an issue where there is no binding appellate authority or legislation, then it is within the authority of that court, and even its duty, to resolve the issue before it consistent with the court's understanding of the governing law. Here, where there is no indication of the Supreme Court's antipathy to collective responsibility, we perceive our role as one to determine what the Supreme Court would do if faced with the problem before us. Roadway Express, Inc. v. Director, Div. of Taxation, 50 N.J. 471, 475 (1967), app. dism. 390 U.S. 745, 88 S.Ct. 1443, 20 L.Ed.2d 276 (1968); State v. Dolton, 146 N.J. Super. 111, 115 (App.Div.), certif. den. 74 N.J. 252 (1977). The denial of potential liability by Namm was as much a policy statement as our recognition, refinement and application of the recognized tort principles discussed herein. The rejection of these theories which have been developed in states with views of tort law similar to our own would be an unwarranted deviation from what we perceive to be a course already charted by our Supreme Court. Not to follow this course would constitute the very "policy shift" decried both in Namm, 178 N.J. Super. at 35, and the dissent.

Insofar as the central issue of collective responsibility is concerned, the Supreme Court stated in Salomon v. Eli Lilly & Co., supra, that

... we neither approve nor disapprove of Namm v. Charles E. Frosst & Co., supra. In light of our decision to remand the matter to the trial court, we need not pass on validity of any of the potential causes of action or defenses. [98 N.J. at 61].

Such a statement cannot be read as precluding our disagreement with our brethren in Namm.

We look to the past decisions of our Supreme Court to determine whether some form of collective responsibility would be antithetical to principles applied in related fields. We note first that where the issue is not the identity of the manufacturer of a product, but rather the identity of the defendant which *622 caused a particular injury, the Supreme Court has not hesitated to shift the burden of proof to defendants to exculpate themselves. Anderson v. Somberg, 134 N.J. Super. 1 (App.Div. 1973), aff'd 67 N.J. 291 (1975), cert. den. 423 U.S. 929, 96 S.Ct. 279, 46 L.Ed.2d 258 (1975). Similarly, where a plaintiff is unable to identify which of several successive carriers damaged plaintiff's property, the Supreme Court placed the burden upon the carriers to come forward and exculpate themselves. NOPCO v. Blaw-Knox Co., 59 N.J. 274 (1971). Also, in a recent toxic tort case, the Supreme Court in Ayers v. Jackson Tp., 106 N.J. 557, 585-586 (1987), noted in dictum that in mass exposure litigation where identification of the culpable defendant presents a causation problem, resort might be had to the alternative liability theory expressed in Summers v. Tice, 33 Cal.2d 80, 199 P.2d 1 (1948), a case in which plaintiff could not prove which defendant was responsible for his injury, and under those special facts the burden of proof was placed upon defendants to disprove causation. Indeed, our Supreme Court has been in the forefront of jurisdictions to recognize and to protect those injured by the wrongful acts of others. See, e.g., Kelly v. Gwinnell, 96 N.J. 538 (1984); Henningsen v. Bloomfield Motors, 32 N.J. 358 (1960). We, therefore, have no reason to suppose that the Supreme Court would reject all theories of collective responsibility, provided the rights of the defendant manufacturers to exculpate themselves are scrupulously protected. Cf. Ferrigno v. Eli Lilly & Co., supra.

B.

There are four basic theories upon which some measure of industry-wide responsibility has been based: (1) concert of action, (2) alternative liability, (3) enterprise or industry-wide liability, and (4) the market-share modification of enterprise or alternative liability. We will briefly examine each theory, citing some relevant cases expounding the principles.

*623 1.

The concert of action theory is premised upon the substantial assistance of various producers of a product to each other to accomplish a tortious result. The parties

in pursuance of a common plan or design to commit a tortious act, actively take part in it, or further it by cooperation or request, or ... lend aid or encouragement to the wrongdoer, or ratify and adopt the wrongdoer's acts done for their benefit.... [W. Keaton, D. Dobbs, R. Keaton & D. Owen, Prosser & Keaton on the Law of Torts, § 46 at 323 (5th ed. 1984)].

The concert of action theory is codified in Restatement, Torts 2d, § 876 at 315, and was applied in Abel v. Eli Lilly & Co., supra, 418 Mich. at 336-339, 343 N.W.2d at 176, and in Bichler v. Eli Lilly & Co., 55 N.Y.2d 571, 436 N.E.2d 182, 450 N.Y.S.2d 776 (1982). The "concert of action" is akin to a conspiracy, a label placed upon the misrepresentation and suppression of health hazard information concerning asbestos in Nicolet v. Nutt, 525 A.2d 146, 150 (Del. 1987).

2.

The alternative liability theory is applied where one of a group of tortfeasors is responsible, in which case the burden shifts to the other defendants to exculpate themselves. If they fail to do so, they are liable. See Anderson v. Somberg, supra. This theory is supported by Restatement, Torts 2d, § 433B(3) at 441-442:

Where the conduct of two or more actors is tortious, and it is proved that harm has been caused to the plaintiff by only one of them, but there is uncertainty as to which one has caused it, the burden is upon each such actor to prove that he has not caused the harm.

Comments g and h elaborate upon the theory.

g. The rule stated in Subsection (3) applies only where it is proved that each of two or more actors has acted tortiously, and that the harm has resulted from the conduct of some one of them. On these issues the plaintiff has still the burden of proof. The rule stated has no application to cases of alternative liability, where there is no proof that the conduct of more than one actor has been tortious at all. In such a case the plaintiff has the burden of proof both as to the tortious conduct and as to the causal relation.

h. The cases thus far decided in which the rule stated in Subsection (3) has been applied all have been cases in which all of the actors involved have been joined as defendants. All of these cases have involved conduct simultaneous in time, or substantially so, and all of them have involved conduct of substantially *624 the same character, creating substantially the same risk of harm, on the part of each actor. It is possible that cases may arise in which some modification of the rule stated may be necessary because of complications arising from the fact that one of the actors involved is not or cannot be joined as a defendant, or because of the effect of lapse of time, or b