Per IRS Instructions for Form 1120-S, page 22:

Schedule K.

Schedule K is a summary schedule of all shareholders’ shares of the corporation’s income, deductions, credits, etc. All corporations must complete Schedule K.

Schedule K-1 shows each shareholder’s separate share. Give each shareholder a copy of the Shareholder’s Instructions for Schedule K-1 (Form 1120-S) or specific instructions for each item reported on the shareholder’s Schedule K-1.

Attach a copy of each Schedule K-1 to the Form 1120-S filed with the IRS. Keep a copy for the corporation’s records and give each shareholder a copy.

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