What Are 13F Filings? Complete Guide to Reading Hedge Fund Holdings
SEC Form 13F is a quarterly report that reveals what the world's biggest hedge funds and institutional investors actually own. Here's how to read them, what they reveal, and what they don't.
What Is SEC Form 13F?
Form 13F is a quarterly filing required by the U.S. Securities and Exchange Commission (SEC) for all institutional investment managers who exercise discretion over $100 million or more in qualifying securities. The name comes from Section 13(f) of the Securities Exchange Act of 1934.
In practice, this means hedge funds, mutual funds, pension funds, insurance companies, and registered investment advisors must publicly disclose their long equity positions every quarter. As of 2026, approximately 5,500 institutional managers file 13F reports, covering trillions of dollars in assets.
What's Inside a 13F Filing?
Each 13F filing is essentially a snapshot of a fund's long equity portfolio on the last day of the quarter. It includes:
- Issuer name and class — The company and type of security (common stock, preferred, etc.)
- CUSIP number — Unique identifier for each security
- Number of shares — Total shares held at quarter end
- Market value — Dollar value of the position at quarter end (not cost basis)
- Investment discretion — Whether the manager has sole, shared, or other discretion
What's NOT in a 13F Filing
This is critical to understand — 13F data has significant blind spots:
How to Read a 13F Filing: Step by Step
Step 1: Find the filing on SEC EDGAR
Go to EDGAR Full-Text Search, enter the fund name, and filter by form type 13F-HR (the full holdings report). Ignore 13F-NT — that's just a notice of filing elsewhere.
Step 2: Sort by position value
Large funds may hold thousands of positions. Focus on the top 10-20 by market value — these represent the highest-conviction bets. Remember: "value" is market value at quarter end, not cost basis.
Step 3: Compare quarter-over-quarter
The real signal is in the changes. Compare current filing to the previous quarter: What's new? What was increased? What was sold entirely? A 45% position increase by Citadel tells you far more than the absolute share count.
Step 4: Look for consensus
A single fund buying a stock is noise. When 5+ elite funds independently open new positions in the same stock, that's a meaningful signal. Our Consensus Engine automates this analysis.
13F Filing Timeline
Understanding the calendar is critical for interpreting 13F data:
| Quarter End | Filing Deadline | Data Reflects |
|---|---|---|
| March 31 | May 15 | Q1 positions |
| June 30 | August 14 | Q2 positions |
| September 30 | November 14 | Q3 positions |
| December 31 | February 14 | Q4 positions |
Most funds file close to the deadline — expect the bulk of filings in the last week before each due date.
Beyond 13F: Other SEC Filings Worth Watching
| Filing | Trigger | Speed |
|---|---|---|
| 13F | $100M+ AUM, quarterly | 45-day delay |
| 13D | 5%+ ownership with activist intent | 10 days |
| 13G | 5%+ ownership, passive | 45 days |
| Form 4 | Insider buys/sells | 2 business days |
Form 4 is the fastest signal — insiders must report trades within 2 business days. 13D filings are particularly interesting because they signal activist intent — the fund isn't just investing, it wants to change something.
Common Mistakes When Using 13F Data
Treating it as a buy list
A 13F shows what a fund held 45+ days ago. The fund may have already sold. It's a research input, not a trade signal.
Ignoring position sizing
A $5M position in a $60B fund is a rounding error. Focus on positions that are 2%+ of a fund's portfolio — those represent real conviction.
Forgetting about hedges
A fund showing a large NVDA long position might be fully hedged with puts. 13F only shows the long side.
How AI Whales Uses 13F Data
We process every 13F filed with the SEC and filter for funds with 10%+ portfolio exposure to AI, semiconductor, and hardware stocks. Currently, 400+ funds meet this threshold.
For each stock in our universe, we calculate a Whale Sentiment Score (0-100) based on net institutional buying, quarter-over-quarter fund count changes, and ownership percentage shifts. Our Consensus Engine identifies stocks where 3+ elite funds independently opened new positions — the strongest signal in 13F data.
Start tracking institutional flows in AI stocks
See what 400+ AI elite funds are buying and selling, updated quarterly.