Blog

From the blog.

Guides, case studies, and sharp takes on SEC filings, institutional flows, and the art of following the smart money.

Basics·Apr 14, 2026·6 min read

How to read a 13F filing — and what it actually tells you

Every quarter, thousands of institutional managers file their holdings with the SEC. Most investors ignore them. Here's why that's a mistake, and how to start.

Strategy·Apr 8, 2026·8 min read

Cluster buying: when multiple funds pile into the same stock

When three or more independent super-investors initiate a position in the same ticker within the same quarter, history suggests something is worth noticing.

Insiders·Mar 30, 2026·5 min read

Form 4 explained: what insider purchases really signal

Corporate insiders buy their own stock for one reason: they think it's going up. Parsing Form 4 data cuts through the noise and isolates the meaningful moves.

Case Study·Mar 22, 2026·7 min read

Berkshire's Apple trim: what $77B of conviction still looks like

Berkshire reduced its Apple stake for the third consecutive quarter. The position is still their largest by far. Here's what the filing actually says.

Pitfalls·Mar 15, 2026·4 min read

The 45-day lag problem — and how to work around it

13F filings are due 45 days after quarter-end. By the time you see the data, the trade is old. But there are ways to use delayed data intelligently.

Markets·Mar 5, 2026·9 min read

The 2023 energy rally every 13F watcher saw coming

Five independent super-investors added to energy in Q4 2022. The sector returned +37% in H1 2023. This is what cluster analysis looks like in practice.