When any investor crosses 5% ownership of a public company, securities law requires them to disclose it to the SEC. Schedule 13D indicates intent to influence — activist campaigns, board fights, strategic reviews. Schedule 13G indicates passive accumulation — an index fund or long-only holder quietly building a position. Telling the two apart is the whole game.
Track who is buying, automatically
Fund Positioning Monitor delivers 13F institutional holdings and 13D/G activist stakes as a clean, scheduled CSV+JSON feed.
Activist vs. passive: why the form matters
A 13D is the “smart money is getting loud” filing — the filer is on record wanting change. A 13G is the “smart money is getting big, quietly” filing. Used alongside Form 4 insider activity and 13F institutional positions, new 5%+ stakes are one of the most-watched ownership disclosures in the market.
The free way: EDGAR
These filings are public on EDGAR. One practical gotcha: in EDGAR’s full-text search the form values are SCHEDULE 13D and SCHEDULE 13G (not “SC 13D”), and amendments (13D/A, 13G/A) come through as their own filings. Pulling them in bulk and keeping activist (13D) separate from passive (13G) is the part that takes real work.
What you want out of each filing
The useful fields are the filer, the issuer and ticker, the filing date, whether it’s a 13D or 13G (activist vs. passive), and a link back to the source. A clean dataset labels each row so you can scan for new activist positions without reading every filing.
The shortcut: a labeled 13D/G feed
A maintained feed tags every new filing as an activist stake (13D) or a passive 5% stake (13G), in CSV + JSON, every row linked to sec.gov. That activist/passive split is exactly what powers the activist-moves view in our Whale Tracker.
Skip the plumbing — get a clean, labeled feed
SEC Filing Monitor turns EDGAR into one event-labeled feed — Form 4, 8-K, Schedule 13D/G, 13F quarterly context and Form NT — delivered as CSV + JSON on a schedule, with every row carrying a event_label and a link back to its sec.gov source. See plans & pricing, or download a free sample (real Form 4, 8-K and 13D/G rows plus daily digests).
Factual public SEC EDGAR data only. Not real-time, not individualized, not a trading signal, and not financial, legal, or investment advice. Filing monitoring of public data. Not affiliated with or endorsed by the U.S. SEC.
Related guides
- Export SEC Form 4 insider trading data to CSV
- Monitor SEC 8-K filings for material events
- SEC Filing Monitor — all five datasets in one feed
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