WhaleWisdom

What it is

WhaleWisdom is a database of what institutions told the SEC they owned. Its spine is Form 13F — the quarterly holdings report every manager with more than $100 million in Section 13(f) securities must file — parsed back to the quarter ending 31 March 2001 and joined to the filings around it: Schedule 13D/G, Form 4 insider transactions, N-PORT mutual fund and ETF constituents since 2019, and searches over Form ADV, Form D, Form 144 and N-CEN.

On top sit the query surfaces — a 13F stock screener, a fund performance search, an overlap matrix, a heat map, an options search over disclosed call and put positions, and a backtester that runs a fund or a group of funds as a portfolio. There is no survivorship bias: delisted securities and defunct funds are still in there.

Pricing

What the paid tiers sell is history and allowance, not features. Free gets the trailing two years of 13F; Standard opens 2001 onward for 50 funds and 50 stocks every 90 days; Pro raises that to 200 and 200; only Enterprise is uncapped and adds nightly FTP files.

Annual billing is the discount, not the default: the pricing page opens on a quarterly toggle, so Standard reads $90 and Pro $150, which is $360 and $600 a year against the $300 and $500 annual rates. There are no trial accounts at all — the vendor says so and points you at the free tier.

Data & coverage

The core is US, because 13F is US. Two features reach past it — a Global Holdings dashboard sold from Standard up, and an international short-position reporting tool — but both sit behind a login, so this card does not state which countries they cover.

Prices appear only as context. Backtests run on total-return prices, which include dividends and will not match a closing print, and "Estimated Avg Price Paid" is the vendor's own word for a guess built from the average price over a quarter.

Integrations

The API is an HTTP GET against a single /shell/command endpoint, with the command and its arguments passed as a JSON args parameter — holdings, holders, the two comparison commands, export and the lookups. Output is HTML by default, with .json and .csv variants. Requests are signed with an HMAC-SHA1 digest over the args and timestamp, or authenticated by session cookie in a browser. The cap is 20 requests a minute, and an interactive shell builds the calls.

There is no official Python client — the docs offer a Python 3 sample, not a library — and nothing named whalewisdom on PyPI. No webhooks, no MCP server. The Excel add-in and the emailed CSV export are the routes out for non-programmers.

Limitations

• 13F is filed up to 45 days after quarter end and most managers wait. A position you read in mid-February was held on 31 December and may have been sold in January.
• It is a long-only, US-only picture, and the gaps are legal rather than editorial. Short positions must not be reported and must not be netted against longs; written options are excluded; shares traded on non-US exchanges are excluded. A fund that is flat a name can look long it. Small positions vanish too — a manager may omit a holding of fewer than 10,000 shares that is also worth less than $200,000.
• 13F is filed at the company level, so for a manager running several funds you cannot tell which fund holds the position.
• Parsing is automatic and fast, and the vendor admits the trade-off, telling you to check the original filing when a number looks wrong.
• The free window is quoted three ways on the vendor's own pages — two years on pricing, the last eight quarters excluding the current one in the API docs, nine quarters in the FAQ.
• The product does not stop at the filings. WhaleIndex publishes ranked stock lists rebalanced after each filing deadline, WhaleScore ranks funds as candidates to follow, and the marketing is explicitly about replicating hedge fund portfolios. That is a list to act on rather than a dataset, under a disclaimer saying none of it is advice. The API is the half that hands you the filings and leaves the conclusion alone.
• Scripting the site outside the API is prohibited and can get the account suspended.

Alternatives

Quiver Quantitative carries 13F as one dataset among many disclosure feeds and sells a cheaper key, but with nothing like this history depth. GuruFocus wraps the same guru filings in thirty years of fundamentals and its own valuation models. Capitol Trades covers congressional disclosures rather than institutional ones, free. Unusual Whales adds the options tape. The rest of the category is at insider, 13F and congressional trade trackers.