No quarterly disclosure gets read more closely than Berkshire Hathaway's Form 13F. Within minutes of each filing hitting SEC EDGAR, headlines announce what Berkshire bought and sold. Most of those headlines are written in a hurry, and some of them are wrong in predictable ways. This guide shows how to go straight to the source, read the filing correctly, and avoid the standard mistakes.
Why Berkshire's 13F matters
Berkshire Hathaway is required to file because it is an institutional investment manager with far more than $100 million in US-listed 13(f) securities. Under Section 13(f) of the Securities Exchange Act, such managers must report their long US equity holdings within 45 days after each calendar quarter ends. The SEC's Form 13F FAQ covers the rule in detail.
Two things make Berkshire's filing unusually informative compared with most hedge fund filings. The portfolio is concentrated, with a handful of positions dominating the total, so changes are meaningful rather than noise. And the holding periods are long, often measured in years or decades, which softens the biggest weakness of 13F data: the reporting lag. A fast-trading fund may be out of a position before its filing is public. Berkshire's positions are usually still there.
The filing also marks an era change. Warren Buffett handed the chief executive role to Greg Abel at the start of 2026 while remaining chairman, which gives each new filing an extra question to answer: what does the portfolio look like as the transition beds in.
Where to find the filing
Berkshire files under CIK 0001067983. The fastest route is the EDGAR company search: enter Berkshire Hathaway or the CIK, then filter on form type 13F-HR. Each filing page includes the cover page and the information table, which EDGAR renders both as raw XML and as a readable table.
Filings arrive on a predictable rhythm. The deadline is 45 days after quarter end, which puts the four filings in mid-February, mid-May, mid-August and mid-November, shifted to the next business day when the date falls on a weekend or holiday. Berkshire, like most large filers, tends to file close to the deadline.
If you prefer a friendlier view, Dataroma presents Berkshire's holdings and quarterly activity in clean tables, and WhaleWisdom adds history and comparisons. Both are built from the same EDGAR filings, so anything important should be verified against the original.
How to read the quarterly changes
Pull the latest filing and the prior one, then match positions by CUSIP. Classify each into new buys, adds, trims and exits, and always compare share counts rather than dollar values. A position's reported value moves with the stock price, so a rising value does not mean Berkshire bought anything.
Weight matters more than count. Berkshire's equity portfolio is famously top-heavy. Long-running core positions such as Apple, American Express, Coca-Cola, Bank of America and Chevron have dominated the filing for years, and a small percentage change in one of them can involve more money than an entire new position further down the list. Read the filing in two passes: first the big holdings for any change at all, then the bottom of the table for new names.
New positions get the headlines for good reason. As one example, Berkshire's Q1 2026 filing disclosed new positions including Alphabet, Delta Air Lines and Macy's, each traceable to the information table of the filing itself. When a firm known for decade-long holding periods starts a position, the entry is worth studying even though the filing arrives weeks after the purchases.
What Berkshire's 13F does not show
The filing covers long positions in US-listed 13(f) securities only. Several important parts of the Berkshire picture live elsewhere.
Cash and Treasury bills. Berkshire's cash pile is one of its most discussed numbers, and it never appears in the 13F. It is disclosed in the quarterly 10-Q and annual 10-K reports, filed under the same CIK on EDGAR.
Foreign-listed holdings. Positions listed only on non-US exchanges do not appear. Berkshire's long-standing BYD stake, listed in Hong Kong, was never in the 13F and its changes were disclosed through Hong Kong exchange filings. Its stakes in the five large Japanese trading houses are likewise disclosed outside the 13F.
Wholly owned businesses. GEICO, BNSF, the energy companies and dozens of other operating subsidiaries are not portfolio positions and never appear. The 13F covers only the marketable securities portfolio.
Who made each decision. The filing does not distinguish stock picks made by Buffett from those made by the investment managers Todd Combs and Ted Weschler. Smaller positions are commonly attributed to the two managers by observers, but the filing itself never says.
One more wrinkle: confidential treatment. The SEC can allow a manager to omit a position from the public filing while it is still being built, with disclosure following later. Berkshire has used this mechanism in the past, notably while accumulating its stake in Chubb, which was revealed in May 2024 after quarters of speculation about a hidden position. So a Berkshire 13F is occasionally incomplete on the day it is published, with the missing piece arriving in a later filing or amendment.
Following Berkshire without fooling yourself
The lag is the first discipline. A February filing shows the portfolio as of December 31. Prices have moved since, and in rare cases the position has too. Buying a stock purely because it appeared in the filing means paying a different price than Berkshire did, sometimes a much higher one after the announcement pop.
The size mismatch is the second. Berkshire manages hundreds of billions of dollars. Its opportunity set is limited to very large companies, and its position sizing logic does not transfer to a small portfolio. What does transfer is the research lead: a new Berkshire position is a well-vetted candidate for your own analysis of the business, its pricing power and its valuation.
The third discipline is context across managers. Berkshire is one voice, an exceptionally good one, but still one. When a Berkshire new buy also shows up as a new buy or an add at other respected funds in the same quarter, the case for spending your research time on that company strengthens. That cross-fund view is exactly what a single filing cannot give you, and building it by hand means repeating the delta analysis for every fund you follow, every quarter.
The Smart-Money 13F Consensus Report puts Berkshire's filing in that context: it distills the latest filings of six top managers, Berkshire included, into one ranked consensus table. Get the free preview.
DataSignals Lab publishes data and research. This is not investment advice.
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