The short answer

What it reportsInformation about cash, stock, or other property from an acquisition of control or the substantial change in capital structure of a corporation.
Amounts to reportOver $1,000
To the recipient(To Shareholders) January 31, (To Clearing Organization) January 5
To the IRS, on paperFebruary 28
To the IRS, electronicallyMarch 31

If one arrives

Usually a taxable exchange of your shares. The form is issued by the corporation, not your broker.

The form is how a payer tells the IRS what it paid. Its absence is not permission — income you received is reportable whether or not a form covers it, and a threshold decides only who must file, never what you owe.

This page is for educational purposes only and does not constitute tax, legal, or financial advice. It covers United States federal reporting. Consult a qualified tax professional about your situation.

Official sources