BP joins Sun Microsystems, Cisco and IBM on the list of companies that had personal information leaked when a laptop was stolen from Ernst & Young in January, The Register reports.

Ernst & Young reportedly distributed a letter to all of BP’s 38,000 U.S. workers, informing them that their names and Social Security numbers were contained in a stolen laptop, according to The Register.

Though personal information on all 38,000 was leaked, the company said the file containing the information did not say what was contained within, and the computer was password protected, according to the Register.

The stolen laptop is the same machine that contained personal information on Sun, IBM and Cisco workers, the Register reports. Ernst & Young also recently lost four additional laptops in Miami, according to The Register, but it did not detail which specific customers may have had information stored on the machines.

The company has largely remained mum on the subject, saying only that the computer that contained BP/Cisco/IBM/Sun personal information was protected with a password, The Register reports.

Though no definite figures have been released as to how many people were affected, and to what extent, The Register estimates that since it has been confirmed the breach exposed all current and former IBM staffers who spent time working overseas, at least 100,000 people had information compromised in that one incident alone.

For related coverage from CIO sister publication CSO, read Stolen Fidelity Laptop Contained Info on 196,000 HP Staffers.

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