moatshark My

Learn

Why moatshark

moatshark started because the free sites for following great investors were hard to use on a phone, and stopped at the 13F. It uses the same public SEC filings, then goes further, and shows what fund fees cost you along the way.

At a glance

  • The great value investors’ 13F holdings, with buys and sells each quarter · Managers
  • Shares a 13F can’t show: overseas holdings from the managers’ US fund filings (N-PORT) · What a 13F misses
  • The managers’ own trades since their last 13F (Form 4) and 5% stakes (13D/13G) · Latest moves
  • Look-through earnings: each manager’s share of the profits it owns, by year and by quarter · Berkshire’s
  • How each portfolio’s mix has changed, every quarter back to 2013, with renames linked · By quarter
  • Your own portfolio seen as an owner, and which managers it’s most like · My portfolio
  • Follow managers, and filter the whole site to them · My moatshark
  • Every table as CSV, JSON and Markdown, free, and an AI assistant connector · AI connector
  • What fees cost you, trackers vs active funds, ISAs, pensions and UK tax, in plain English · Getting started
  • No adverts, no pop-ups, no account needed, and built for phones

Coming from Dataroma?

Dataroma has served value investors well for years. It tracks more managers than we do (81 “superinvestors” at the last count, against our 64) and has its own real-time and insider-buying pages. If you use it, moatshark will feel familiar: managers, their holdings, and their buys and sells. What’s different is everything in the list above that goes beyond the 13F: the overseas holdings from fund filings, the managers’ own Form 4 trades, look-through earnings, the history with renames linked, your own portfolio, free downloads, and a site with no adverts that works on a phone. We add managers each quarter; tell us who’s missing.

Other 13F sites follow every filer, often with paid tiers for history and alerts. moatshark stays deliberately small: a hand-picked list of long-term value investors, each checked by hand, with the context to understand why they own what they own.

Built to be checked

  • Every holding links back to the SEC filing it came from.
  • Share classes are combined, stock splits adjusted, and renamed companies linked (Google to Alphabet, Priceline to Booking), so a rename doesn’t look like a sale.
  • Methods are explained in how moatshark works, and every number can be downloaded.

What moatshark isn’t

It isn’t investment advice and doesn’t recommend anything. Filings are snapshots published weeks after the quarter ends, and our processing can contain errors, so check anything important against the filing itself. moatshark is independent and isn’t affiliated with any manager shown, or with any other site mentioned here.