Did Mickey Mouse lose your Social Security number?

That's what some people who own Disney stock are wondering after receiving an alarming letter in the mail.

Many northeast Ohioans own Disney stock to enjoy benefits and discounts for shareholders, and grandparents often buy a share for grandchildren.

But there is word of a security breach after New York's Mellon Bank has reported the possible theft of 4 million names and Social Security numbers, reported NewsChannel5 consumer reporter John Matarese.

Mellon Bank was a transfer agent for Disney shares and is now alerting some shareholders there Social Security numbers may be compromised, and that they should sign up for credit monitoring.

However, if you bought your Disney shares through a brokerage firm, your name is usually not on the shares and should be safe.

If you didn't receive a letter, you have nothing to worry about, Matarese said.