Methodology

What this site is

13F Research surfaces stocks that may warrant further research by aggregating the quarterly disclosed positions of a curated universe of prominent hedge funds and institutional investors. The premise: when several unrelated, well-resourced managers independently converge on the same stock in the same quarter, that convergence is worth knowing about — especially if the price hasn't already run away.

It is a starting point for research, not a substitute for it. Nothing here is investment advice, and no signal on this site is a recommendation to buy or sell anything.

The core signal: convergence

Every quarter, institutional managers with over $100M in US equities must disclose their long positions on SEC Form 13F-HR, due 45 days after quarter-end (most funds file on the deadline). We parse the filings of a curated universe of funds — value, macro, activist, long/short, and tech/growth managers — and compare each fund's positions to its prior quarter. A small number of firms are tracked for their 13D/13G filings only and excluded from the convergence signals: either their 13F no longer reflects a live portfolio, or their book spans thousands of largely market-making positions that would dilute a signal built on multi-fund agreement. The Funds page lists both tiers.

A long signal requires 3 or more funds buying the same stock in the same quarter — a new position or any share-count increase. A short signal requires 3+ funds each reducing a position by more than 50% or exiting entirely. Stocks with both a long and a short signal appear in Mixed Signals — divergent conviction, shown separately.

Share classes of the same company (e.g. GOOG/GOOGL) are merged into one signal — a fund holding both classes counts once. ETFs are excluded entirely: funds hold them for beta and hedging, not stock selection.

Conviction score

Each buying fund contributes to the stock's score:

• Base: 1.0 per fund
• New position: +0.5
• Large add (shares more than doubled): +0.25
• × size multiplier: 0.5 + min(position %, 3) / 3— from 0.5× for a tiny sliver up to 1.5× when the position is 3%+ of the fund's equity book

The size multiplier is the heart of the score: a manager putting 4% of their portfolio into a name is making a categorically different statement than a multi-manager platform holding a 0.03% position. Each fund's "% of Fund" is shown on the stock detail pages.

Short signals are scored the same way (base 1.0 × size multiplier), weighted by the fund's prior-quarter position — dumping a large position is a louder exit signal than trimming a small one. Long Ideas with a score of 4.0 or higher appear in the main table; lower-scoring signals move to the collapsed Watchlist.

The price filter

13F data is stale by design — holdings are as of quarter-end, published up to 45 days later. The price filter separates ideas where the market has already reacted: a long signal passes while the stock has outperformed SPY by lessthan 10 points since quarter-end; a short signal passes while it has underperformed by less than 10 points. Signals that fail move to the "Already Moved" sections — the thesis may be intact, but the easy move likely already happened.

Prices refresh daily, so stocks migrate between sections as returns change. A stock that was Already Moved and pulls back into range gets a ↩ badge for 14 days — the funds were right once, and the price has reverted.

Corroborating signals

Five independent data layers are shown alongside the core signal. None of them affect the conviction score — they are context for your own research, each linked to its primary source on the detail pages.

Data freshness

Exclusions & limitations

• 13F filings only cover US-listed long positions — short books, swaps, and non-US holdings are invisible.
• Managers below $100M AUM are exempt from filing; positions can change materially between quarter-end and the filing date.
• Options positions (calls/puts) are tracked on a separate tab with a lower 2-fund threshold — 13F reports notional share equivalents, not capital at risk, so they never mix with equity signals.
• ETFs are excluded from equity signals.
• Congressional amounts are ranges; Senate filing links require accepting the Senate's access agreement.
• This site is informational only and is not investment advice.