Continental Insurance Company (Continental) (defendant) offered its employees retiree benefits, including a monthly Health Care Allowance (HCA). Beginning in 1991, Continental began offering an early-retirement program known as the Voluntary Special Retirement Program (VSRP), which included Continental’s own version of a monthly HCA. Continental’s materials on the VSRP incorporated a 1992 Retirement Guide, which set forth the terms of Continental’s standard retiree-benefit plan. The 1992 Retirement Guide included a clause reserving Continental’s right to amend or revoke retiree benefits at any time. In meetings with potential early retirees, Continental orally represented that the HCA benefit was a lifetime benefit. Continental said nothing about the revocability of the HCA benefit. In 1995, CNA Financial Corporation (CNA) (defendant) acquired Continental. In 1998, CNA decided that the HCA benefit under the VSRP would be revoked as of January 1, 1999. Thereafter, 347 Continental employees who had accepted early retirement under the VSRP in 1992 (plaintiffs) sued CNA for terminating their HCA benefits. The plaintiffs claimed wrongful denial of benefits under (1) the Employee Retirement Income Security Act (ERISA), 29 U.S.C. § 1001, et seq.; (2) equitable estoppel; and (3) breach of fiduciary duty. The district court granted summary judgment in favor of CNA. The plaintiffs appealed.