Warren Buffett's 13F Filings: Why It's Really Berkshire's Report

Search for "Warren Buffett's 13F filing" and you will land on Berkshire Hathaway's quarterly holdings report, not a filing by Buffett as an individual. That is not a simplification: EDGAR actually has a filer registered under Buffett's own name, and its public filings report no holdings at all.

This post explains why that is, which filing actually carries the holdings people are looking for, and how to pull that data as JSON instead of reading the SEC's raw filing index by hand.

Buffett has his own EDGAR filer, and it reports nothing

Section 13(f) of the Securities Exchange Act of 1934 requires any institutional investment manager with discretion over $100 million or more in qualifying securities to file a Form 13F each quarter. "Manager" is a broad legal term, and it can cover an individual as well as a company. EDGAR has long carried a filer registered as "BUFFETT WARREN E" (SEC filer number 28-554), and over the years it has submitted its own 13F-HR cover pages.

Those filings are marked as 13F combination reports, which is the format used when the holdings tied to the filer are actually reported by another manager in the same filing group. The cover page lists Berkshire Hathaway Inc. (filer number 28-4545) as that other manager, and the information table total for Buffett's own filer comes out to $0 in almost every quarter on record. One is not zero: a filing covering a 2004 quarter shows a small information table total of roughly $685,000, which is a rounding-scale amount next to Berkshire's reported portfolio. Every other filing checked for this post, across 2002 through 2007, reports a $0 total.

In plain terms, Buffett holds a 13F filer registration because he personally has investment discretion as Berkshire's chairman, but the substance of what he oversees is reported through Berkshire Hathaway's own corporate filer, not his individual one.

Where the real holdings actually are

Berkshire Hathaway Inc. files its 13F-HR under its own CIK, 1067983, the same number used for every other SEC filing the company makes, including its 10-Ks and 8-Ks. That is the filing that contains the information table most people are actually trying to find when they search for "Buffett's 13F": every qualifying US listed stock position, by CUSIP, with share count, market value and voting authority.

Berkshire Hathaway's 13F: What It Shows and What It Hides covers that filing in detail, including the SEC confidential treatment provision that has let Berkshire delay naming a new position for a quarter or more in recent years. The rest of this post stays focused on the Buffett-versus-Berkshire filer question and the mechanics that apply to either one.

When any 13F, including Berkshire's, is due

A 13F is due within 45 days after the end of each calendar quarter, whether the filer is an individual, a hedge fund or a conglomerate like Berkshire:

Berkshire has generally filed close to that deadline rather than early, which means a position shown in a given quarter's 13F can already be close to six weeks old, and may have changed again since. 13F Filing Deadlines and Why Holdings Data Is Always a Bit Stale covers the full deadline table and what that lag means for reading the data.

What a 13F does and does not show, for either filer

Whether you query under Buffett's personal filer number or Berkshire's own CIK, the form has the same legal scope: it only covers "Section 13(f) securities," a defined list the SEC maintains.

• Included: US exchange listed common stock, listed call and put options, certain listed convertible securities, and ETF shares.
• Not included: Berkshire's wholly owned operating subsidiaries (insurance, railroads, utilities, manufacturing), cash and short term Treasury bills, most bonds, most foreign listed shares, and any short position of any kind.

That means a 13F, under any filer name, never adds up to a full picture of what Berkshire owns as a business. It is a snapshot of the publicly traded stock portfolio only.

Pulling Berkshire's 13F holdings as data

Browsing a single 13F-HR on EDGAR works if you only want one quarter. Comparing quarters, or checking which other large holders also report the same stock, is slow by hand because the information table is published as XML.

SecFeed parses every 13F information table into rows and lets you query by manager CIK. To pull Berkshire's reported holdings for the quarter ended June 30, 2026, sorted by value:

curl "https://secfeedapi.com/v1/form-13f/holdings?cik=1067983&period=06-30-2026" \
  -H "Authorization: Bearer YOUR_API_KEY"

Each row returns the issuer, CUSIP, reported value, share count and voting authority split:

{
  "filer_cik": 1067983,
  "filer": "BERKSHIRE HATHAWAY INC",
  "period": "06-30-2026",
  "issuer": "EXAMPLE TECHNOLOGIES INC",
  "cusip": "000000000",
  "value": 150000000000.0,
  "shares": 900000000.0,
  "sh_prn": "SH",
  "put_call": null,
  "vote_sole": 900000000.0
}

The cover page, including the reporting period and whether a filing is marked as an amendment, comes from /v1/form-13f?cik=1067983. In Python, you can pull two consecutive quarters and diff them by CUSIP to see what changed:

from secfeed import Client

sf = Client("YOUR_API_KEY")
q2 = {r["cusip"]: r for r in sf.holdings_13f(cik="1067983", period="06-30-2026")}
q1 = {r["cusip"]: r for r in sf.holdings_13f(cik="1067983", period="03-31-2026")}
new_positions = [c for c in q2 if c not in q1]
exits = [c for c in q1 if c not in q2]
print("new:", new_positions)
print("exited:", exits)

For the underlying field reference, see the 13F-HR manager quarterly holdings dataset page, and for a worked walkthrough of aggregating a fund's positions and computing portfolio weights, see Get a fund's 13F portfolio holdings by CIK.

Frequently asked questions

Does Warren Buffett file his own 13F?

He has a registered SEC filer number, and historical filings under that number exist, but their information tables total $0 in nearly every quarter on record. The holdings associated with his name are reported under Berkshire Hathaway Inc.'s separate CIK, 1067983.

What is the difference between Warren Buffett's 13F and Berkshire Hathaway's 13F?

Buffett's personal filer submits a combination report cover page that names Berkshire Hathaway Inc. as the manager actually reporting the holdings. Berkshire's own filing, under its own CIK, is the one with the real information table.

Where can I see Berkshire Hathaway's current stock holdings?

On SEC EDGAR, under CIK 1067983, filtering for form type 13F-HR. SecFeed also parses that filing's information table into structured rows through /v1/form-13f/holdings.

How current is Berkshire's 13F data?

Positions are as of the last day of the calendar quarter and can be published up to 45 days later, so a published 13F can already be weeks out of date, and Berkshire may have changed the position since.

Does Berkshire's 13F show everything the company owns?

No. It only covers Section 13(f) securities, which means publicly traded US stocks and some related instruments. It does not show Berkshire's wholly owned subsidiaries, its cash and Treasury bill holdings, most bonds, or any short positions.