O'Brien Greene & Co. Inc BRK/B — BERKSHIRE HATHAWAY INC CL B

Ownership history in O'Brien Greene & Co. Inc  ·  30 quarters on record

AI Ownership Summary

O'Brien Greene & Co. Inc reported BERKSHIRE HATHAWAY INC CL B (BRK/B) in 30 quarterly 13F filings from 2023 Q4 through 2026 Q1. Peak portfolio weight reached 5.28% in 2025 Q1. The latest visible filing shows BRK/B at 3.78% of the fund.

This page tracks quarterly shares, estimated market value, portfolio weight, filing dates, and disclosure-aligned stock prices directly from SEC EDGAR 13F filings. Older history is available after unlock; the visible window still shows the most recent pattern.

What this BRK/B ownership page tells you

This page is designed to answer the real investor question behind a 13F filing: how meaningful was O'Brien Greene & Co. Inc's position in BERKSHIRE HATHAWAY INC CL B, and how did that conviction change over time? You can read the holding window, peak weight, latest reported size, disclosure timing, and quarter-by-quarter changes without piecing the story together from raw SEC rows.

Freshest filing
Latest Reported Filing
2026 Q1

BRK/B was reported at 3.78% of portfolio in the most recent visible filing.

High-water mark
Peak Conviction
5.28% in 2025 Q1

Peak weight helps separate a token disclosure from a real conviction holding the fund genuinely cared about.

Time in book
Holding Window
2023 Q4 to 2026 Q1

Longer holding windows often tell a very different story from short-lived tactical trades or one-quarter experiments.

Decision context
Why It Matters
Position size beats headlines

Knowing that a fund owned a stock is useful. Knowing whether it was a 0.20% placeholder or a true high-conviction position is where the signal actually starts.

BRK/B stock page O'Brien Greene & Co. Inc fund profile O'Brien Greene & Co. Inc full holdings
How O'Brien Greene & Co. Inc held BRK/B — position size vs. price
% of Fund (quarterly)
📋 Quarterly Holdings History 10 quarters  ▾
Quarter Action Sold % After 3M Timing Shares Change Chg % % of Fund Mkt Value Filed Price (Filed)
2026 Q1 REDUCED — — — 27,834 -85 -0.3% 3.78% $13.3M 2026-05-06 $469.32
2025 Q4 REDUCED — — — 27,919 -390 -1.4% 4.17% $14.0M 2026-02-05 $503.89
2025 Q3 REDUCED — — — 28,309 -503 -1.7% 4.38% $14.2M 2025-11-10 $496.98
2025 Q2 REDUCED — — — 28,812 -760 -2.6% 4.58% $14.0M 2025-08-06 $468.91
2025 Q1 REDUCED — — — 29,572 -1,328 -4.3% 5.28% $15.7M 2025-05-12 $514.30
2024 Q4 REDUCED — — — 30,900 -697 -2.2% 4.55% $14.0M 2025-02-03 $464.61
2024 Q3 REDUCED — — — 31,597 -2,506 -7.3% 4.53% $14.5M 2024-11-15 $470.28
2024 Q2 ADDED — — — 34,103 +1,075 +3.3% 4.39% $13.9M 2024-08-12 $430.39
2024 Q1 ADDED — — — 33,028 +300 +0.9% 4.57% $13.9M 2024-05-02 $400.60
2023 Q4 REDUCED — — — 32,728 -165 -0.5% 4.10% $11.7M 2024-02-02 $390.75
20 older quarters hidden  —  Sign in free or upgrade to Premium to see full history

🏢 Other funds also holding BRK/B

As of 2026 Q1 — sorted by position size

TETRAD CORP 92.15% 1922 Investment Co LLC 3Y 7Y 84.86% CHECK CAPITAL MANAGEMENT INC/CA 3Y 7Y 52.8% Cook & Bynum Capital Management, LLC 3Y 7Y 42.7% Templeton & Phillips Capital Management, LLC 3Y 36.02% Aquamarine Zurich AG 3Y 34.57% Ardent Capital Management, Inc. 3Y 32.73% Asset Management Advisors, LLC 3Y 7Y 32.43% United American Securities Inc. (d/b/a UAS Asset Management) 3Y 7Y 31.97% Pacifica Capital Investments, LLC 3Y 7Y 30.79%

FAQ About O'Brien Greene & Co. Inc and BRK/B

These are the practical questions this page is built to answer before you even open the full history table.

How long has O'Brien Greene & Co. Inc reported owning BRK/B?

O'Brien Greene & Co. Inc reported BRK/B across 10 quarterly 13F filings, from 2023 Q4 through 2026 Q1.

What was the largest reported BRK/B position in O'Brien Greene & Co. Inc's portfolio?

The largest reported portfolio weight for BRK/B was 5.28% in 2025 Q1.

What is the latest reported BRK/B position on this page?

The most recent filing on this page is 2026 Q1, when O'Brien Greene & Co. Inc reported 27,834 shares, equal to 3.78% of portfolio, with an estimated market value of $13.3M.

What does the chart on this BRK/B ownership page compare?

The chart compares O'Brien Greene & Co. Inc's quarterly BRK/B portfolio weight with the stock's indexed share price, so you can see whether the fund was building, trimming, or holding the position as price moved.

How well did O'Brien Greene & Co. Inc time their BRK/B position?

Based on 13F filing dates vs. subsequent BRK/B price moves, O'Brien Greene & Co. Inc correctly timed 12 out of 29 reported position changes (41%). The annualised alpha on BRK/B relative to SPY over the holding period was -3.2%.

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