BLAIR WILLIAM & CO/IL: BRK-B position timeline

BLAIR WILLIAM & CO/IL held 483,586 BRK-B shares at 2026-06-30 per its 13F-HR filed 2026-08-11.

the latest 13F is the newest step

1. period ended2026-06-30

   13F 483,586 shares

   Change vs previous 13F -11,736 shares

   0.63% of the 13F portfolio, value $241,981,741.

   13F-HR 0001104659-26-093821 filed by BLAIR WILLIAM & CO/IL
   Filed 2026-08-11 (acceptance time not in the bulk data set), ingested 2026-10-06 09:57:27 UTC

   Acceptance time not in the bulk data set (spec §4.2).

2. period ended2026-03-31

   13F 495,322 shares

   Change vs previous 13F +48,260 shares

   0.68% of the 13F portfolio, value $237,358,312.

   13F-HR 0001104659-26-057897 filed by BLAIR WILLIAM & CO/IL
   Filed 2026-05-08 (acceptance time not in the bulk data set), ingested 2026-10-06 09:58:43 UTC

   Acceptance time not in the bulk data set (spec §4.2).

3. period ended2025-12-31

   13F 447,062 shares

   Change vs previous 13F +1,828 shares

   0.6% of the 13F portfolio, value $224,715,783.

   13F-HR 0001104659-26-015563 filed by BLAIR WILLIAM & CO/IL
   Filed 2026-02-17 (acceptance time not in the bulk data set), ingested 2026-10-07 03:01:36 UTC

   Acceptance time not in the bulk data set (spec §4.2).

4. period ended2025-09-30

   13F 445,234 shares

   Change vs previous 13F +2,637 shares

   0.6% of the 13F portfolio, value $223,836,762.

   13F-HR 0001104659-25-109927 filed by BLAIR WILLIAM & CO/IL
   Filed 2025-11-12 (acceptance time not in the bulk data set), ingested 2026-10-07 03:02:25 UTC

   Acceptance time not in the bulk data set (spec §4.2).

5. period ended2025-06-30

   13F 442,597 shares

   Change vs previous 13F +21,843 shares

   0.6% of the 13F portfolio, value $215,000,361.

   13F-HR 0001104659-25-070274 filed by BLAIR WILLIAM & CO/IL
   Filed 2025-07-24 (acceptance time not in the bulk data set), ingested 2026-10-07 18:23:11 UTC

   Acceptance time not in the bulk data set (spec §4.2).

6. period ended2025-03-31

   13F 420,754 shares

   Change vs previous 13F +1,635 shares

   0.68% of the 13F portfolio, value $224,085,428.

   13F-HR 0001104659-25-046545 filed by BLAIR WILLIAM & CO/IL
   Filed 2025-05-09 (acceptance time not in the bulk data set), ingested 2026-10-07 18:25:06 UTC

   Acceptance time not in the bulk data set (spec §4.2).

7. period ended2024-12-31

   13F 419,119 shares

   Change vs previous 13F +11,262 shares

   0.55% of the 13F portfolio, value $189,978,484.

   13F-HR 0001104659-25-011872 filed by BLAIR WILLIAM & CO/IL
   Filed 2025-02-12 (acceptance time not in the bulk data set), ingested 2026-10-07 18:25:55 UTC

   Acceptance time not in the bulk data set (spec §4.2).

8. period ended2024-09-30

   13F 407,857 shares

   Change vs previous 13F not available

   0.55% of the 13F portfolio, value $187,720,478.

   13F-HR 0001104659-24-116499 filed by BLAIR WILLIAM & CO/IL
   Filed 2024-11-12 (acceptance time not in the bulk data set), ingested 2026-10-07 18:26:56 UTC

   Acceptance time not in the bulk data set (spec §4.2).