12.2 C Corporations and Shareholder Transactions

C Corporations as Separate Taxpayers

Area V of the 2026 AICPA REG Blueprint covers federal taxation of entities, weighted 23-33% and the heaviest tax area on REG. It includes C corporation taxable income, tax liability at the flat 21% corporate rate, allowable credits, current-year net operating loss (NOL) and capital loss limits, and state and local tax issues. The core idea is separation: a C corporation files Form 1120, pays tax on its own taxable income, and shareholders then analyze dividends, stock basis, or gain separately.

That separation creates the classic double-tax pattern, but REG tests it through facts. A corporation may earn income, incur nondeductible expenses, distribute cash, or sell property. The candidate must decide which items affect taxable income, which affect earnings and profits (E&P), and which affect the shareholder.

Book Income to Taxable Income

A C corporation TBS often starts with an adjusted book trial balance. Taxable income is not book income. Permanent differences affect taxable income but never reverse (federal income tax expense, tax-exempt municipal interest, 50% of meals, fines and penalties). Temporary differences affect timing and reverse later (MACRS vs. book depreciation, accrued expenses not yet deductible, warranty reserves). Schedule M-1 (or M-3 for larger entities) reconciles the two.

Shareholder Distributions and the E&P Ordering

A cash distribution is not automatically a dividend. Apply the source ordering: (1) to the extent of current and accumulated E&P, it is dividend income; (2) beyond E&P, it reduces stock basis as a tax-free return of capital; (3) once basis is exhausted, the excess is capital gain.

Worked example: a shareholder with $4,000 stock basis receives a $10,000 distribution from a corporation with $6,000 of current E&P. Result: $6,000 dividend, $4,000 reduces basis to zero, and $0 gain — but if the distribution were $12,000, the final $2,000 would be capital gain. E&P is a tax measure of distribution capacity and is distinct from book retained earnings.

If the corporation distributes appreciated property, the corporation recognizes gain as if it sold the property at FMV, and the shareholder measures the distribution by FMV reduced by any liability assumed. A frequent trap is taxing only the shareholder and forgetting the corporate-level gain.

Formations, Liabilities, and State Concepts

Under Section 351, a transfer of property to a corporation solely for stock is tax-free if the transferors control at least 80% of voting and other stock immediately afterward. Exceptions: boot (cash or non-stock property) triggers recognized gain up to its value, and liabilities relieved in excess of basis trigger gain. The corporation takes a carryover basis in the property; the shareholder's stock basis equals contributed basis minus liabilities relieved plus gain recognized.

The Blueprint also includes nexus, apportionment, and allocation. Nexus asks whether a state has sufficient connection to tax the corporation. Apportionment divides business income using provided factors (sales, property, payroll); REG supplies the factors and formula, so apply the given numbers rather than importing a memorized threshold.

Exam workflow: build three columns — corporation, shareholder, state. Put taxable-income adjustments in the corporate column, dividend/basis/gain in the shareholder column, and nexus/apportionment only in the state column. Separate columns prevent the classic error of using a shareholder rule to compute the corporate return.

Losses, the DRD, and Other Recurring C-Corp Mechanics

A C corporation net operating loss generated in 2018 or later carries forward indefinitely with no carryback, and the deduction is limited to 80% of taxable income computed before the NOL. Corporate capital losses never offset ordinary income; they offset only capital gains, carrying back three years and forward five. Candidates routinely confuse these with the more generous individual rules, so anchor on the entity type before applying a limit.

The dividends-received deduction (DRD) is a frequent simulation input. A corporation that owns less than 20% of the payer deducts 50% of dividends received; ownership of 20% to less than 80% allows a 65% deduction; 80% or more generally allows a 100% deduction. The DRD is subject to a taxable-income limitation that can be overridden when the deduction creates or increases an NOL — a layered rule TBSs love to test.

Finally, watch the accumulated earnings tax and personal holding company tax as penalty regimes that discourage hoarding earnings, and remember that estimated tax for large corporations and the timing of the Schedule M-2 E&P rollforward both surface in review tasks. Each of these sits squarely in the corporate column, never the shareholder column, reinforcing the separation discipline.