The IRS has imposed restrictions in the amount that a C Corporation may deduct for Charitable contributions made to a Charitable Foundation. In general, the corporations have no restrictions on the amount of charitable contributions that they make. However, obtaining a current year tax deduction is another matter.
The IRS rules state the the Corporation is entitled to deduct up to a maximum of 10% of a Corporations net taxable income without consideration of NOL and Charitable contribution. In other words, calculate the taxable income without deduction of charitable contribution, and a maximum limit is 10% of this taxable income.
Assuming a Corporation has no taxable income, then that Corporation would not be able to deduct charitable contributions for that calendar year, instead it will simply carry this deduction over to the future years subject to the normal charitable deductions limitations.