The US filings behind every stock, explained

What is SEC Form 4?

Form 4 is the filing an officer, a director or an owner of more than 10% of a US public company's shares sends to the SEC when their holding in the company changes, for example when they buy or sell its stock. It is due before the end of the second business day after the trade, and it shows the date, a one-letter transaction code, the number of shares, the price and how many shares the insider holds afterwards.

Form 4 transaction codes: what P, S, A, M, F and G mean

Every row on a Form 4 carries a one-letter code set by the SEC that says what the transaction was. P is a purchase on the open market or in a private deal and S is a sale, and these are the two where an insider chose to buy or sell. A is a grant or award, M is an option exercised, F is shares held back to pay the exercise price or tax, and G is a gift.

What is SEC Form 144?

Form 144 is the notice a person files with the SEC when they plan to sell restricted or control shares under Rule 144 and the sale in any three months will be more than 5,000 shares or $50,000. The person is most often an officer, a director or a large holder of the company. It is filed at the same time the sell order goes to the broker, so it often appears before the sale shows up on a Form 4.

Form 4 vs Form 144: what each insider filing means

Form 4 reports an insider trade after it happens, within two business days, and covers purchases, sales, grants and option exercises. Form 144 gives notice of a planned sale of restricted or control shares, filed when the sell order goes to the broker. For one sale by an officer you will often see both: the Form 144 first, then the Form 4 that shows what was actually sold.

Rule 10b5-1 trading plans: how insiders trade on a schedule

A Rule 10b5-1 plan lets an insider set up a schedule of trades in advance, at a time when they hold no inside information, so later trades under it can go ahead even if they learn something. Since 2023 a director or officer must wait at least 90 days after adopting a plan, and up to 120 days, before the first trade, and Form 4 has a checkbox for trades made under a plan.

What is Form 13F?

Form 13F is the quarterly report an institutional investment manager files with the SEC once it manages at least $100 million in US-listed shares and other 13(f) securities. It lists those holdings as they stood on the last day of the quarter, and it is due within 45 days after the quarter ends, so the holdings are already weeks old when the public reads them.

13F filing deadlines for 2026 and 2027

A Form 13F is due 45 days after each calendar quarter ends. When the 45th day falls on a Saturday, a Sunday or a federal holiday, the deadline moves to the next business day. Holdings at 30 September 2026 are due on Monday, 16 November 2026, and holdings at 31 December 2026 on Tuesday, 16 February 2027, because 14 February is a Sunday and 15 February is Washington's Birthday.

Schedule 13D and 13G: who must report a 5% stake

Anyone who comes to own more than 5% of a class of a US public company's voting shares must report it to the SEC on Schedule 13D or Schedule 13G. A holder who may try to influence or control the company files the longer 13D within five business days. Passive investors, and qualified institutions such as banks, brokers, insurers and registered advisers, can file the shorter 13G.

13D vs 13G: the differences and the deadlines

Schedule 13D and Schedule 13G both report a stake of more than 5% in a US public company. The 13D is for holders who may seek to influence or control the company: it is due in five business days, every amendment in two, and it must state their plans. The 13G is for passive holders and qualified institutions: it is shorter, and qualified institutions file it 45 days after the quarter.

How members of Congress report stock trades: the House periodic transaction report

Under the STOCK Act, members of the US House must report a trade in a stock, bond or other security worth more than $1,000 on a periodic transaction report, or PTR. It is due within 30 days of learning of the trade and no later than 45 days after it, and it covers trades by the member's spouse and dependent children too. The report gives the amount as a range, such as $1,001 to $15,000, and never the exact sum.

What is short interest, and how is it reported?

Short interest is the number of a company's shares that have been sold short and not yet bought back, counted on a settlement date. Under FINRA Rule 4560, brokers report their short positions in every stock twice a month, by 6 p.m. Eastern on the second business day after each settlement date, and FINRA publishes the totals about seven business days after the settlement date.

FINRA short interest reporting dates for 2026

FINRA sets two short interest settlement dates each month, one in the middle and one at the end. Brokers report by 6 p.m. Eastern on the second business day after each settlement date, and FINRA publishes the figures about seven business days after it. The settlement of 30 October 2026 is due on 3 November and published on 10 November 2026.