WILMINGTON, Del. (Reuters) - Employees of U.S. nuclear power firm Westinghouse Electric Co LLC, which is bankrupt and reeling from a failed reactor project, got a nasty surprise recently: in the eyes of the U.S. government’s pension insurer, its retirement plan has a massive shortfall.

The Vogtle Unit 3 and 4 site, being constructed by primary contactor Westinghouse, a business unit of Toshiba, near Waynesboro, Georgia, U.S. is seen in an aerial photo taken February 2017. Georgia Power/Handout via REUTERS

While bankrupt companies often have big pension deficits, the vast majority flag the underfunding years in advance of filing for Chapter 11. By contrast, the Westinghouse Electric Co Pension Plan, which has about 9,700 participants, appeared fully funded in its most recent report to the Department of Labor in 2015.

The Pension Benefit Guaranty Corp estimated the pension plan is unfunded by $937 million, according to previously unreported court filings in August.

The shortfall is conditional on Westinghouse using the tools of bankruptcy to terminate the plan. In that case, the PBGC would step in, take over the plan and apply its more conservative accounting.

Westinghouse spokeswoman Sarah Cassella said the company has not told the agency it will end the plan.

Westinghouse is considering bids for the company, and has asked potential buyers to assume the pension would be maintained and that annual contributions would continue near current levels, according to a person familiar with the bidding process.

However, Pittsburgh-based Westinghouse, which is owned by Toshiba Corp 6502.T of Japan, is expected to attract private-equity investors who tend to want as few obligations as possible.

One actuary who advises pension plans said the PBGC claim may encourage buyers to insist Westinghouse terminate the plan.

“It highlights the poorly funded status and so no one really wants to take on the defined benefit plan,” said Greg Reardon, of consulting firm Cheiron Inc.

POTENTIAL DISCONTENT

The PBGC claim exceeds the plan’s $926 million in assets and according to PBGC data it would be among the 10 largest for a pension shortfall, ranking ahead of Trans World Airlines in 2001 and Pan American Air in 1991 and 1992.

The claim stems not from mismanagement or fraud, but the way Westinghouse and the PBGC determine how much is needed today to pay for future pension benefits.

Under Department of Labor rules, Westinghouse is required to assume that a bond portfolio will earn a much higher rate of return than the current market rates, which are used by the PBGC.

The agency’s conservative approach means more money is needed today to pay for retirees. As a result, PBGC claims in bankruptcy cases often catch other creditors off guard, said Joseph House, a principal at Palisades Capital Advisors and former head of the PBGC’s restructuring group.

The company has said in court documents that retaining highly specialized engineers is key to its success, and until it filed for bankruptcy in March the pension was one way to hold on to top talent.

Ending the plan would mean more Westinghouse debt and less for other creditors, and it could mean reduced benefits for the plan’s participants. If the plan is terminated, participants will receive a guaranteed benefit from the PBGC, which currently hits a maximum at about $64,000 a year. Any annual pension payments above that level could be lost, although there are exceptions.

A former Westinghouse executive, who asked not to be identified talking about his former employer, said the PBGC claim came as a shock, given the plan’s funding levels in recent years and conservative investments. “You’re going to have a lot of discontent,” said the executive. “It’s a great tool to keep people tied to the company.”

Westinghouse, however, is in cost-cutting mode. The company said in its recent turnaround plan it would reduce its roughly 11,000 global staff by 7 percent.

In July, two utilities in South Carolina canceled a half-finished nuclear power plant that was meant to be a showcase for Westinghouse’s engineering and design.

The South Carolina project and a similar half-finished plant in Georgia were both billions of dollars over budget and years behind schedule, which contributed to Westinghouse’s bankruptcy.