The law says

“any individual with respect to whom a deduction under section 151 is allowable to another taxpayer”

is not eligible.

Do you know the difference between “allowed” and “allowable”? Maybe you have done some simple returns with rental income, where you had to deduct depreciation even if the tax was already zero. Or if the property was sold, you had to calculate the depreciation that should have been claimed even though some incompetent preparer didn’t do so.

No? Maybe you were absent that day. I think it was in the third week of class. But now you know.