Reversed by published opinion. Judge TRAXLER wrote the opinion, in which Judge NIEMEYER and Judge WILSON joined.
OPINION
Verdelle Blackshear appeals a decision of the district court awarding summary judgment to Reliance Standard Life Insurance Company (“Reliance Standard”) and refusing to disturb the denial of Black-shear’s claim for benefits under a group life insurance policy. For the reasons that follow, we reverse.
I.
Reliance Standard issued a group life insurance policy to Duplin General Hospital that became effective on January 1, 2003. The group policy, which was part of Duplin General’s employee welfare benefit plan, covered both present and future hospital employees. The policy set forth the following benefits schedule:
SCHEDULE OF BENEFITS
NAMES OF SUBSIDIARIES, DIVISIONS OR AFFILIATES TO BE COVERED: None
ELIGIBLE CLASSES: Each active, full-time employee, except any person employed on a temporary or seasonal basis.
WAITING PERIOD:
Present Employees — Exempt*: none Non-exempt*: none
Future Employees- — Exempt*: 180 days Non-exempt*: none
* as defined by the Fair Labor Standards Act, as amended. 1
INDIVIDUAL EFFECTIVE DATE: The first of the Policy month coinciding with or next following completion of the Waiting Period, if applicable.
J.A. 19. The statutorily required Summary Plan Description (“SPD”) issued to the employees included an identical schedule of benefits. See 29 U.S.C.A. § 1022 *637 (West 1999), § 1024(b) (West 1999 & Supp. 2007).
On June 10, 2003, Yerdie Blackshear (“Yerdie”) began working at Duplin General as a nurse and received a copy of the SPD for Duplin General’s employee welfare benefit plan. Verdie died six months later on December 14, 2003. Blackshear, Verdie’s named beneficiary under the policy, filed a claim on January 8, 2004, with Reliance Standard for the life insurance proceeds of $81,078.40. According to the language of both the SPD and the policy itself, non-exempt employees such as Ver-die hired after the issuance of the Policy were not subject to a service waiting period, meaning that the coverage provided by the policy took effect immediately upon Verdie’s employment.
Upon receiving the claim, Reliance Standard contacted the Human Resources Department for Duplin General to verify Ver-die’s non-exempt status and the effective date of her coverage. In a letter dated January 21, 2004, Susan Hayes, Duplin General’s Vice President for Human Resources, wrote that, contrary to the actual language of the policy and the SPD, the “policy should cover all employees for life insurance after six (6) months of employment” and that “[tjhere should be no discrimination between exempt and non-exempt employees.” J.A. 167. On January 26, 2004, Reliance Standard re-issued Dup-lin General’s group policy. The amended policy, which had the same January 1, 2003, effective date, eliminated the distinction between exempt and non-exempt employees and instead imposed a six-month service waiting period for all employees before coverage would take effect. The Individual Effective Date remained the same: “The first of the Policy month coinciding with or next following completion of the Waiting Period.” J.A. 276 (emphasis added).
Reliance then denied Blackshear’s claim on the grounds that Verdie was not insured under Duplin General’s group policy on December 12, 2003, the date of her death, for failure to satisfy the waiting period as defined in the amended policy:
Verdie Blackshear was employed June 10, 2003.... [T]he applicable 6 month Waiting Period of Full-time employment would have been satisfied on December 10, 2003. The scheduled effective date of insurance for Ms. Blackshear was January 1, 2004....
As Verdie Blackshear died prior to the scheduled effective date of her coverage, January 1, 2004, she did not satisfy the eligibility requirements ... and the life insurance coverage- did not go into effect in accordance with the terms of the policy ...
We are aware that due to a clerical error, booklets were printed that did not correctly state the applicable 6 month waiting period of employment. [Duplin General] confirmed in [a] telephone conversation [on] March 5, 2004 and in earlier conversations with our staff that all eligible employees of Dup-lin General Hospital are subject to the 6 month Waiting Period of Full-Time employment and that the original booklets contained an error regarding application of the Waiting Period for non-exempt employees. This error has now been corrected and new booklets have been forwarded to [Duplin General] for distribution to ... eligible employees.
J.A. 109.
Blackshear sought review of the denial of her claim for benefits under Reliance Standard’s appeal review procedure. Reliance Standard concluded that its original determination to deny benefits was proper and denied Blackshear’s appeal. In affirming its denial of benefits, Reliance Standard acknowledged that “an error had *638 occurred in the initial Policy and booklet printing with regard to the applicable ‘WAITING PERIOD,’ ” and classified the omission of the waiting period for nonexempt employees in the original policy and SPD as a “clerical error” that was inconsistent with “the original intention of the Policy.” J.A. 93. In addition to its conclusion that “original intention” prevails over unambiguous language in the policy and the SPD, Reliance Standard also relied upon the “General Provisions” section of the policy that provides “[cjlerical errors in connection with the Policy or delays in keeping records for the Policy, whether by you, us, or the Plan Administrator ... (1) will not terminate insurance that would otherwise have been effective; and (2) will not continue insurance that would otherwise have ceased or should not have been in effect.” J.A. 93.
Ultimately, Blackshear filed this action against Reliance Standard under ERISA, seeking review of the denial of benefits.
See
29 U.S.C.A. § 1132(a)(1)(B) (West 1999). The parties filed cross-motions for summary judgment. Applying a modified abuse of discretion standard of review,
see Bynum v. Cigna Healthcare of North Carolina, Inc.,
On appeal, Blackshear argues that the clear and unambiguous language originally set forth in the SPD and the policy controls and afforded Verdie insurance coverage immediately upon employment without a waiting period. Reliance Standard’s disregard of this unambiguous language, contends Blackshear, amounted to an abuse of discretion.
II.
In reviewing the denial of benefits under an ERISA plan, a court’s first task is to consider
de novo
whether the relevant plan documents confer discretionary authority on the plan administrator to make a benefits-eligibility determination.
See Firestone Tire & Rubber Co. v. Bruch,
Typically, once it has determined that the abuse of discretion standard applies, the reviewing court turns to the question of whether the administrator’s exercise of discretion was reasonable as determined by the application of a number of well-established factors.
See Booth,
Because Reliance Standard insures the very plan it administers, the district court concluded that it was operating under a conflict of interest. Rebanee Standard does not challenge the district court’s ap-pbcation of the modified abuse of discretion standard under the circumstances, and we agree that this standard of review was appropriate for judicial review of decisions in which Reliance Standard was
actually exercising
its discretionary authority under the plan.
See Bynum,
With these principles in mind, we turn to the substantive issues.
III.
Broadly speaking, “ERISA plans are contractual documents which, while regulated, are governed by established principles of contract and trust law.”
Haley v. Paul Revere Life Ins. Co.,
*640 It is undisputed that, at the time of Verdie’s death, the plan documents relevant to Duplin General’s group life insurance clearly and unequivocally afforded coverage for Verdie and other non-exempt employees without a waiting period. Thus, in concluding that, contrary to the written instruments, Verdie was in fact subject to a 180-day waiting period, Reliance Standard was not resolving an ambiguity in the policy’s language but reading a clear and unambiguous provision out of the written plan documents.
Nevertheless, Reliance Standard contends that we should not disturb its decision to deny benefits for two reasons. First, Reliance Standard asserts that the failure to include a service waiting period in the original policy was a “clerical error” and that the policy permitted it unilaterally to amend or correct “clerical errors” in the terms of the policy. Second, Reliance Standard argues that the omission of a waiting period was the result of a scrivener’s error and that the doctrine of equitable reformation permits the policy to be corrected retroactively to reflect the actual intent of the contracting parties. We conclude that the denial of benefits cannot stand under either theory.
A.
According to Reliance Standard, the “clerical errors” provision set forth in the group policy permitted it to make its benefits-eligibility determination based on extrinsic evidence of the contracting parties’ original intent instead of the written terms of the policy. After receiving Blackshear’s claim and reviewing correspondence between Duplin General and Reliance Standard before the original policy was issued, Reliance Standard amended the policy to include a service waiting period for all employees and then relied upon the amended version of the policy to deny Blackshear’s claim for benefits. Thus, we must decide whether it was permissible for Reliance Standard to deny Blackshear’s claim based on a retroactive amendment to the policy.
The group policy is part of an “employee welfare benefit plan,”
see
29 U.S.C.A. § 1002(1) (West 1999), which is “exempt from the statutory vesting requirements that ERISA imposes on pension benefits.”
Wheeler v. Dynamic Eng’g, Inc.,
Nevertheless, the terms of a plan may create vested rights in welfare benefits even though the employer is under no obligation to do so.
See Wheeler,
Accordingly, we must determine whether Blackshear’s right to life insurance proceeds vested before Reliance Standard issued the amended policy. In
Wheeler,
we referred to general state insurance law in concluding that under a group medical insurance policy, benefits vest at the time that the covered loss occurs.
See
In rejecting the denial of benefits based on a post-death amendment to a group life insurance policy, the Seventh Circuit explained that the employer could not
retroactively modify a life insurance policy after the insured’s death so as to take away the life insurance proceeds due a beneficiary at the date of the insured’s death ... [A]t [the insured’s] death [the beneficiary] became entitled to the ... insurance proceeds, not based on ERISA’s vesting principles, but based on general insurance law which provides that a beneficiary’s right to insurance proceeds vests on the date of the insured’s death.... A later modification, even one which is retroactive, can have no effect on a beneficiary’s claim to benefits.
Filipowicz,
We also conclude that the “clerical errors” provision does not dictate a different result. This provision provided that “[clerical errors in connection with the Policy or delays in keeping records for the Policy, whether by you, us, or the Plan Administrator ... will not continue insurance that would otherwise have ceased or should not have been in effect.” J.A. 93. Reliance Standard argues that the failure to include a waiting period in the original *642 policy was a “clerical error” upon which Blackshear cannot rely to “continue insurance that ... should not have been in effect.” Assuming such an omission would even qualify as a “clerical error,” and assuming that this provision relates in some way to the sponsor’s general right to amend or eliminate the policy at anytime (which it does not), we believe the language still in no way authorizes the administrator to divest benefits that are already due by amending, modifying or correcting the language of the policy itself.
In sum, Reliance Standard may not deprive Blackshear of vested benefits based on the waiting period in the amended policy. We conclude that its application of the “clerical errors” provision to arrive at such a result was an abuse of discretion.
B.
Having concluded that Reliance Standard may not deny life insurance benefits to Blackshear by amending the policy, we turn to the question of whether it can achieve the same result via the equitable doctrine of reformation.
Reliance Standard argues that regardless of what the plan dictates, the omission of the waiting period resulted from a scrivener’s error and that the policy should be enforced according to the true intent of the contracting parties. In denying benefits, Reliance Standard indeed based its decision on its view of the intent of the contracting parties to apply a service waiting period before coverage became effective for individual employees. We conclude that Reliance Standard had no authority to reform the policy in this manner and that, in any event, equitable reformation is not appropriate under these circumstances.
The doctrine of equitable reformation permits a court to exercise its equitable powers to reform a contract to correct a mutual mistake of fact or a scrivener’s error that fails to capture the true intent of the contracting parties. “In contract law, a scrivener’s error, like a mutual mistake, occurs when the intention of the parties is identical at the time of the transaction but the written agreement does not express that intention because of that error; this permits a court acting in equity to reform an agreement.” 27 Richard A. Lord,
Williston on Contracts
§ 70:93 (4th ed.). The party seeking reformation of the contract must present evidence that is “clear, precise, convincing and of the most satisfactory character that a mistake has occurred and that the mistake does not reflect the intent of the parties.”
International Union v. Murata Erie N. Am., Inc.,
The salient point for our purposes, however, is that reformation, whether it is based upon scrivener’s error or mutual mistake, is most decidedly a remedy available
in a court of equity.
“The purpose of proving a mistake is to correct what has become an erroneous situation. Equity will act to bring an erroneous writing into conformity with the true agreement ... A mistake, in and of itself, has no legal effect.” 27
Williston on Contracts
§ 70:17. The doctrine of equitable reformation does not apply in the context of an administrator’s interpretation of an ERISA plan; the administrator cannot simply “reform” a plan to correct what it unilaterally perceives to be a mistake or error contained in the plan’s written terms. Rather, reformation, like other forms of equitable relief, must be requested by the party seeking to reform the contract and granted by a court.
See Audio Fid. Corp. v. Pension Benefit Guar. Corp.,
We also reject Reliance Standard’s suggestion that the district court in fact applied the doctrine of equitable reformation. In no sense did the district court reform the group policy. The district court saw the issue as “whether Reliance Standard abused its discretion in its application of the ‘clerical error’ provisions of the Policy.” J.A. 330. The district court’s focus, therefore, was on Reliance Standard’s application of a specific provision contained in the plan; to the extent the court considered and discussed evidence of Duplin General’s original request that the group policy include a waiting period, it did so to determine whether there was substantial evidence in the record to support application of the “clerical error” provision. Of course, the district court’s omission of any discussion of the doctrine of equitable reformation is not surprising in view of Reliance Standard’s failure to request or refer to such relief in its pleadings or its legal memoranda submitted with the cross-motions for summary judgment.
Even though Reliance Standard did not afford the district court an opportunity to pass on this issue below, we need not return the case for the district court to address the propriety of equitable reformation. We conclude that, under the circumstances of this case, it would be inappropriate for the court to exercise its equitable powers to reform the policy. To do so would undercut important fundamental aims of ERISA. For example, reforming the policy to deprive Blackshear of benefits that are due based on extrinsic documents would foster uncertainty about employee benefits rather than furthering ERISA’s goal of “ensuring] that an employee’s rights and obligations can be readily ascertained from the plan documents.”
Cinelli,
The fundamental requirement that plan participants have sufficient notice of their rights under an ERISA plan drove our decisions in
Pierce v. Security Trust Life Insurance Co.,
Finally, equitable reformation in the circumstances of this case is inappropriate in view of ERISA’s protection of vested rights. Pension benefit plans create benefits that vest according to statute and are non-forfeitable.
See Nachman Corp. v. Pension Benefit Guar. Corp.,
Accordingly, we conclude that equitable reformation is not appropriate.
IV.
For the foregoing reasons, we reverse the decision of the district court and remand for judgment to be entered in favor of Blackshear.
REVERSED
Notes
. The Fair Labor Standards Act of 1938 imposes minimum wage and maximum hour requirements. See generally 29 U.S.C.A. §§ 201-219 (West 1998 & Supp.2007). Certain types of employees are exempt from these provisions. See 29 U.S.C.A. § 213. The parties agree that the decedent in this case was a "non-exempt” employee.