Top 10 Holdings of Primecap Management
What the latest 13F actually shows
A 13F is a snapshot taken up to 45 days after the quarter closed, and it shows long US equity positions only. Read in that light, here is what Primecap Management reported holding.
| Ticker | Position | Value | Weight |
|---|---|---|---|
| MU | MICRON TECHNOLOGY INC | $22.18 billion | 13.1% |
| LLY | ELI LILLY & CO | $11.00 billion | 6.5% |
| INTC | INTEL CORP | $10.51 billion | 6.2% |
| KLAC | KLA CORP | $6.20 billion | 3.7% |
| GOOGL | ALPHABET INC | $5.31 billion | 3.1% |
| FLEX | FLEX LTD | $3.79 billion | 2.2% |
| AZN | ASTRAZENECA PLC | $3.43 billion | 2.0% |
| NVDA | NVIDIA CORPORATION | $3.42 billion | 2.0% |
| BIIB | BIOGEN INC | $3.27 billion | 1.9% |
| AMZN | AMAZON COM INC | $2.85 billion | 1.7% |
Latest updates
- October 7, 2026, 11:32 AM ET
The filings behind this page have been updated. Refreshed to the Q2 2026 filing; largest position is MU at $22.18 billion.
The dataTicker Position Value Weight MU MICRON TECHNOLOGY INC $22.18 billion 13.1% LLY ELI LILLY & CO $11.00 billion 6.5% INTC INTEL CORP $10.51 billion 6.2% KLAC KLA CORP $6.20 billion 3.7% GOOGL ALPHABET INC $5.31 billion 3.1% FLEX FLEX LTD $3.79 billion 2.2% AZN ASTRAZENECA PLC $3.43 billion 2.0% NVDA NVIDIA CORPORATION $3.42 billion 2.0% BIIB BIOGEN INC $3.27 billion 1.9% AMZN AMAZON COM INC $2.85 billion 1.7% As reported for Q2 2026.Source: SEC Form 13F filings · InsiderBuying.com - October 7, 2026, 11:00 AM ET
Something changed in the underlying record. Refreshed to the Q2 2026 filing; largest position is MU at $22.18 billion.
- October 7, 2026, 10:31 AM ET
Refreshed to the Q2 2026 filing; largest position is MU at $22.18 billion.
- October 7, 2026, 10:26 AM ET
Refreshed to the Tue Jun 30 2026 00:00:00 GMT+0000 (Coordinated Universal Time) filing; largest position is MU at $22.18 billion.
The concentration
The top 10 positions carry 43% of the disclosed portfolio by value, across 324 reported holdings in total.
MICRON TECHNOLOGY INC alone is 13.1% of it.
Concentration is a choice about conviction and about risk at the same time, and a 13F shows the result without showing the reasoning.
- MU$22.18 billion · 13.1%
- LLY$11.00 billion · 6.5%
- INTC$10.51 billion · 6.2%
- KLAC$6.20 billion · 3.7%
- GOOGL$5.31 billion · 3.1%
- FLEX$3.79 billion · 2.2%
- AZN$3.43 billion · 2.0%
- NVDA$3.42 billion · 2.0%
- Everything else$103.28 billion · 61.1%
What a 13F leaves out
Short positions, cash, bonds, commodities and most non-US listings never appear. A manager who is net short the market can look long-only here.
The filing is also late by construction: positions shown may have been sold weeks before the document became public.
It remains the only mandatory, auditable window into what large managers own, which is why it is worth reading carefully rather than literally.
The bottom line
A snapshot, filed late, of one side of the book. Useful, and not the whole position. Not investment advice. Summarized from public SEC Form 4 and congressional disclosure data.