Investor Diff: What Changed Between This Quarter and Last

Why the Diff Is the Only 13F View That Matters

A single 13F snapshot tells you what a fund owned at a point in time. That's useful the first time you study a manager; after that, the only new information is how the book changed. Did they double down on their biggest position, or trim it? Did they initiate three names at 1% each (experimental) or two at 4% each (conviction)? Did they exit a name they'd owned for 12 quarters? The diff answers those questions and turns 13F data from history into signal.

What the Investor Diff Card Shows

The Investor Diff card compares a selected filer's current 13F to prior-quarter holdings and groups changes into four buckets: new positions (not held last quarter), exits (held last quarter, absent now), adds (existing position increased by >10% of shares), and trims (existing position reduced by >10% of shares). Each entry shows the share change, dollar change, % of AUM change, and the ticker's price action over the quarter so you can see whether the filer was adding into strength or weakness. A "conviction change" column flags positions that crossed the 3%-of-AUM conviction threshold in either direction.

Reading the Changes

Three patterns are the highest-signal. First, adds into weakness by high-conviction managers — if Klarman / Greenblatt / Marks added to a position while the stock dropped 20% in the quarter, that's a much stronger signal than a general 13F "holder" tag. Second, exits after 8+ quarters of holding — long-tenure exits almost always mean a thesis change, and they're worth investigating; the sell happened at quarter-end prices which are usually available, making it a clean case study. Third, cluster across multiple filers — when 5+ top-decile managers all initiate the same name in the same quarter, the underlying setup is genuinely unusual; when 5+ exit, distribution is happening and the name is often due for correction.

Where It Fits

Pair with Investor Holdings for the static book, Institutional Holders for the per-ticker view, and Conviction Components to see how these flows factor into per-name conviction scoring.

Open the Investor Diff card → /app/investors