Barry Scher, a spokesman for Ahold USA in Quincy, Mass., said the company has notified the retirees about the incident by mail but added that information about the number of affected former employees and the kind of data kept on the laptop is not being made public. "We're not giving out any numbers to protect our people," he said.

Scher said the laptop was lost by an employee of Electronic Data Systems Corp., which provides data processing services for the Ahold USA Pension Plan. The laptop was password-protected and contained a file with the personal information of retired participants in the pension plan and of some other former employees of Ahold USA subsidiaries, including Stop & Shop Supermarket Cos., also in Quincy, Mass., according to a company statement.

Kimberly Walton, a spokeswoman for EDS, today acknowledged that the computer was lost amid baggage on a flight after an airline employee asked the EDS worker to check the bag rather than carry it onto the aircraft. "By doing so, that employee violated our company policy," Walton said.

The employee has been disciplined, but Walton would not comment further on whether the person still works for EDS. After the laptop was determined to be lost, the EDS employee did notify the airline and local police about the incident, she said. EDS then told Ahold about what had happened, Walton said.

Scher and Walton would not specify when or where the incident occurred or what airline was involved. Walton said the company has received no reports that any of the data has been used illegally.