# Schedule 13D

Also written Schedule 13G, 13D/G.

*https://stockmarketstack.com/glossary/schedule-13d · next to Insider, 13F & Congressional Trade Trackers*

**Definition:** The SEC filing anyone acquiring beneficial ownership of more than 5% of a registered class of equity makes when they may seek to influence control, due within five business days and amended within two when something material changes. Schedule 13G is its passive twin: the same threshold, a far looser clock, and the difference between them is what the holder says they intend to do.

## How it works

Both schedules answer the same statutory question — who owns a large stake in a US registered class
of equity — and they split on what the holder means to do with it. The trigger is beneficial
ownership of more than five per cent. The choice of form is about control.

**Schedule 13D is the control filing.** A holder who may seek to influence or change control of the
issuer files it, and since the SEC's 2023 amendments the initial filing is due within five business
days of crossing the threshold, down from the ten calendar days that had stood since the early
1970s. Amendments are due within two business days of a material change, and the rules treat an
acquisition or disposition of one per cent or more of the class as material. In practice that means an
activist building a position files repeatedly, every percentage point, and the sequence of amendments
is the readable part: it shows accumulation in near-real time.

**Schedule 13G is the passive filing**, available to holders who are not seeking control and to
qualified institutions reporting in the ordinary course of business. Its deadlines are the opposite
end of the range. A qualified institution has until 45 days after the end of the calendar quarter in
which it crossed five per cent; a passive investor has five business days. Amendments run 45 days
after quarter end where something material has changed. The 2023 rule moved these from an annual
cycle to a quarterly one, with a compliance date of 30 September 2024, and required both schedules to
be filed in a structured, machine-readable format from 18 December 2024 — which is the reason a
programmatic pipeline over 13D/G data has a discontinuity in late 2024.

The consequence is a clock that depends on the holder rather than on the event. An index manager
crossing five per cent on 1 October may not appear in the record until the middle of February. An
activist crossing the same line on the same day is public within the week. Both are compliant.
[When a trade shows up in the public record](https://stockmarketstack.com/guides/when-trades-become-public) lays these deadlines
out beside Form 4 and the 13F.

## What it does and does not establish

A 13D is a statement of position and purpose, not a plan. Item 4 requires the holder to describe its
purpose, and the language is frequently broad enough to cover doing nothing — reserving the right to
acquire more, dispose, or engage with management. A filing is evidence that somebody crossed a
threshold and chose the control form; it is not a commitment to act.

Beneficial ownership is also not the same as shares held outright. It covers voting and dispositive
power, and it can be shared, which is why the same shares appear on more than one schedule and why
naive summation of stakes across filers overstates ownership.

And the group provisions matter for reading counts: holders acting together can be treated as one
person for the threshold, so a stake can become reportable without any single holder buying anything.

## Why it matters here

Of everything in [this category](https://stockmarketstack.com/categories/insider-13f-trackers), 13D amendments are the fastest
signal of a position being built rather than reported — the only filing here that is close to the
event in the way a [Form 4](https://stockmarketstack.com/glossary/form-4) is, and far ahead of the quarterly
[13F](https://stockmarketstack.com/glossary/13f). That makes the question to ask a product a narrow one: does it carry 13D and
13G at all, does it track amendments as a series rather than showing only the latest, and does it
keep the filer's own intent language or reduce it to a percentage?

[WhaleWisdom](https://stockmarketstack.com/tools/whalewisdom) and [StockCircle](https://stockmarketstack.com/tools/stockcircle) carry activist filings beside
fund holdings, [SECForm4](https://stockmarketstack.com/tools/secform4) and [13F-Info](https://stockmarketstack.com/tools/13f-info) surface them in the
ownership record, and [sec-api.io](https://stockmarketstack.com/tools/sec-api-io) sells them as endpoints for people building on
the data. [SEC EDGAR](https://stockmarketstack.com/tools/sec-edgar) has all of it, free and structured, and
[how to get SEC filings as data](https://stockmarketstack.com/how-to/get-sec-filings-as-data) is the way in without a
subscription.

## Where you will meet this

- [WhaleWisdom](https://stockmarketstack.com/tools/whalewisdom.md)
- [SecForm4.com](https://stockmarketstack.com/tools/secform4.md)
- [Stockcircle](https://stockmarketstack.com/tools/stockcircle.md)
- [sec-api.io](https://stockmarketstack.com/tools/sec-api-io.md)
- [13F.info](https://stockmarketstack.com/tools/13f-info.md)
- [SEC EDGAR](https://stockmarketstack.com/tools/sec-edgar.md)
- [2iQ Insider Transactions Data](https://stockmarketstack.com/tools/2iq-insider-data.md)
- [Fintel](https://stockmarketstack.com/tools/fintel.md)
- [GuruFocus](https://stockmarketstack.com/tools/gurufocus.md)
- [Insider Screener](https://stockmarketstack.com/tools/insider-screener.md)

## FAQ

### What actually decides whether a holder files 13D or 13G?

Intent, not size. Both are triggered by crossing five per cent of a registered class. Schedule 13G is available to holders who are passive or who qualify as institutions reporting in the ordinary course of business; a holder who may seek to influence or change control files Schedule 13D instead, and a 13G filer who develops that intent has to move onto 13D.

### Why do two five-per-cent stakes show up months apart?

Because the clocks differ by filer type. An activist crossing the threshold is in the public record within five business days. A qualified institution using Schedule 13G has until 45 days after the end of the calendar quarter in which it crossed. The same ownership fact is news in a week or a season depending entirely on who holds it.

## Sources

1. [SEC Adopts Amendments to Modernize Beneficial Ownership Reporting](https://www.sec.gov/newsroom/press-releases/2023-219) — U.S. Securities and Exchange Commission, 2023-10-10. The five-business-day 13D window and the 13G compliance date of 30 September 2024 are both past and in force, and the release has not been superseded.
2. [Modernization of Beneficial Ownership Reporting, Final Rule (88 FR 76896)](https://www.govinfo.gov/content/pkg/FR-2023-11-07/html/2023-22678.htm) — Securities and Exchange Commission, 2023-11-07
3. [17 CFR 240.13d-1 — Filing of Schedules 13D and 13G](https://www.ecfr.gov/current/title-17/part-240/section-240.13d-1) — Office of the Federal Register, read 2026-09-21

*Last updated 2026-09-21. A reference page, corrected in place — not a dated post.*