The opinion of the court was delivered by: MARVIN E. ASPEN
MARVIN E. ASPEN, District Judge:
Plaintiffs Central States, Southeast and Southwest Areas Pension Fund and Trustee Howard McDougall (collectively "Central States" or the "Fund") bring this two-count complaint against Plymouth Concrete, Inc. ("Plymouth"). Count I seeks the payment of contributions owed for the period of September, 1991 through February, 1992, based on employee work history as reported by Plymouth. Count II seeks the payment of contributions for the period between December 27, 1987 and September 21, 1991, revealed to be owed as the result of an audit of Plymouth's records. Presently before the court is Plymouth's motion for judgment on the pleadings or, alternatively, for summary judgment. We will treat this motion as one for summary judgment and, for the reasons set forth below, it is denied.
I. Summary Judgment Standard
Under the Federal Rules of Civil Procedure, summary judgment is appropriate if "there is no genuine issue as to any material fact and . . . the moving party is entitled to judgment as a matter of law." Fed. R. Civ. P. 56(c). This standard places the initial burden on the moving party to identify "those portions of 'the pleadings, depositions, answers to interrogatories, and admissions on file, together with the affidavits, if any' which it believes demonstrate the absence of a genuine issue of material fact." Celotex Corp. v. Catrett, 477 U.S. 317, 323, 106 S. Ct. 2548, 2553, 91 L. Ed. 2d 265 (1986) (quoting Rule 56(c)). Once the moving party has done this, the non-moving party "must set forth specific facts showing that there is a genuine issue for trial." Fed. R. Civ. P. 56(c). In deciding a motion for summary judgment, the court must read all facts in the light most favorable to the non-moving party. Anderson v. Liberty Lobby Inc., 477 U.S. 242, 254, 106 S. Ct. 2505, 2513, 91 L. Ed. 2d 202 (1986); Griffin v. Thomas, 929 F.2d 1210, 1212 (7th Cir. 1991).
Central States is a multi-employer benefit plan governed by the Employee Retirement Income Security Act of 1974 ("ERISA"), 29 U.S.C. §§ 1001 et seq. Plaintiff Howard McDougall is a Trustee and a fiduciary of the Fund, and brings this action in that capacity. Plymouth is a Michigan corporation and an "employer" and a "party-in-interest" as those terms are defined by, respectively, §§ 1002(5) and 1002(14)(C) of ERISA. Pursuant to a series of collective bargaining and participation agreements, Plymouth agreed to pay monthly contributions to the Fund on behalf of covered its employees. These monthly contributions were to be made on the basis of an employee work history as reported by Plymouth. Additionally, under the terms of the trust agreement, Central States maintained the right to audit the records of participating employers to verify the accuracy and completeness of employee work history reported by employers.
The instant suit is not the first action brought by Central States against Plymouth. On April 5, 1991, the Fund filed suit against Plymouth, seeking contributions on the basis of reported employee work history for the period of July, 1990 through December, 1990. See Complaint P 19, at 6, Central States, Southeast and Southwest Areas Pension Fund v. Plymouth, No. 91-2042 (N.D. Ill. Apr. 5, 1991) ("Plymouth I"). The complaint in Plymouth I alleged that Plymouth reported employee work history for the period between July and December of 1990, but breached the collective bargaining agreement, the Fund trust agreement and a participation agreement "by failing to pay all of the contributions (and interest due thereon) which the employee work history it reported to the Pension Fund revealed to be owed." Id. P 17, at 6. As Plymouth agreed to pay the entire delinquent balance in installments, pursuant to stipulation of the parties, the case was dismissed with prejudice by minute order dated December 12, 1991.
Given the disposition in Plymouth I, Plymouth now moves for judgment on all claims for contributions owed prior to April 5, 1991, arguing that those claims could have been raised in the prior proceeding and, as such, are barred by the doctrine of res judicata.
Under the doctrine of res judicata, "a final judgment on the merits of an action bars further claims by the parties or their privies based on that same action. Gray v. Lacke, 885 F.2d 399, 404 (7th Cir. 1989), cert. denied, 494 U.S. 1029, 110 S. Ct. 1476, 108 L. Ed. 2d 613 (1990); see also Montana v. United States, 440 U.S. 147, 153, 99 S. Ct. 970, 973, 59 L. Ed. 2d 210 (1979); Beard v. O'Neal, 728 F.2d 894, 896 (7th Cir.), cert. denied, 469 U.S. 825, 105 S. Ct. 104, 83 L. Ed. 2d 48 (1984).
Furthermore, the doctrine operates to bar not only those issues that the parties actually litigated, but also any claim that the parties could have raised in the prior proceeding. Gray, 885 F.2d at 404-05; Car Carriers, Inc. v. Ford Motor Co., 789 F.2d 589, 593 (7th Cir. 1986); Illinois Hosp. Ass'n v. Edgar, 765 F. Supp. 1343, 1347 (N.D. Ill. 1991). For this court to apply the doctrine of res judicata to the instant suit, Plymouth must demonstrate: (1) a final judgment on the merits in Plymouth I, the prior action; (2) an identity of the cause of action in both Plymouth I and the current action; and (3) an identity of parties or their privies in the two suits. See Gray, 885 F.2d at 405; Mandarino v. Pollard, 718 F.2d 845, 849 (7th Cir. 1983), cert. denied, 469 U.S. 830, 105 S. Ct. 116, 83 L. Ed. 2d 59 (1984). Central States concedes that the first and third elements are present in this case. Central States' Response to Defendant's Motion for Summary Judgment at 5. Accordingly, we turn to consider the existence of the second requisite, the identity of the cause of action.
The Seventh Circuit has adopted the transactional approach of the Restatement (Second) of Judgments in determining whether the cause of action in the second suit is identical to that set forth in the first. See In re Energy Coop., Inc., 814 F.2d 1226, 1230-31 (7th Cir.), cert. denied, 484 U.S. 928, 108 S. Ct. 294, 98 L. Ed. 2d 254 (1987); Car Carriers, 789 F.2d at 593. Under this approach, the relevant inquiry entails a determination of whether the two actions arise out of "a single core of operative fact." Car Carriers, 789 F.2d at 593. This inquiry is "decidedly fact-oriented. Once a transaction has caused injury, all claims arising from that transaction must be brought in one suit or be lost. Thus, 'a mere change in the legal theory does not create a new cause of action.'" Id. (quoting Alexander v. Chicago Park District, 773 F.2d 850, 854 (7th Cir. 1985)). Further, the determination must be pragmatic:
What factual grouping constitutes a "transaction" . . . [is] to be determined pragmatically, giving weight to such considerations as whether the facts are related in time, space, origin, or motivation, whether they form a convenient trial unit, and whether their treatment as a unit ...