If you've been notified by the IRS either over the phone or by mail that you owe them, that's all the warning you get.
An H&R manager in Southern California has been arrested for using the identities of his former tax preparation clients. Damon Dubose was working as a manager for H&R Block and alledgedly obtained personal information from past clients. He prepared fake tax returns in their names to get refunds and credits and then used the H&R Block Emerald Cards to withdraw the funds from ATMS.
Almost everything you own and use for personal or investment purposes is a capital asset. Capital assets include a home, vehicle, stocks and bonds. When a capital asset is sold, the difference between the amount you paid for the asset and the amount you sold it for is a capital gain or capital loss.