Marc, the IRS definition of income is quite broad, and as others say, this is not a gray area or even a judgment call. Trying to claim it is a gift is foolish and will accepted by the IRS. Of course, if they don't audit you, it may never be discovered. Even if they audit you, it may never be discovered. If your 1040 income is below 100k, you are probably not at much risk for an audit. Still, it's one less thing to worry about if you just report it.