PRIMECAP Management Co·13F Holdings
- Positions
- 227
- Top-10 weight
- 47%
- Largest
- MU · 14%
- Quarter ending
- Jun 30, 2026
- Added
- 67
- Trimmed
- 128
- Sold out
- 2
- Last filed
- Aug 14, 2026
Portfolio
What does PRIMECAP Management Co own?
PRIMECAP Management Co reported 227 long equity positions worth $154.3B for the quarter ending Jun 30, 2026. The largest is MU at 14% of reported value. The ten largest positions make up 47% of the portfolio. Against the prior quarter it added to 67 positions, trimmed 128 and sold out of 2. The latest 13F was filed Aug 14, 2026.
Largest positionsValue · weight
- MUMicron Technology, Inc.$22.2B14% of portfolio
- LLYEli Lilly and Company$11.0B7.1% of portfolio
- INTCIntel Corporation$10.5B6.8% of portfolio
- KLACKLA Corporation$6.2B4.0% of portfolio
- GOOGLAlphabet Inc.$5.3B3.4% of portfolio
- FLEXFlex Ltd.$3.8B2.5% of portfolio
- AZNAstrazeneca PLC$3.4B2.2% of portfolio
- NVDANVIDIA Corporation$3.4B2.2% of portfolio
- BIIBBiogen Inc.$3.3B2.1% of portfolio
- AMZNAmazon.com, Inc.$2.9B1.8% of portfolio
Sector tilt
Which sectors does PRIMECAP Management Co lean on?
Technology (41%) and Healthcare (19%) are the two largest sectors by reported value.
By share of reported value, across 227 classified tickers.
Quarter changes
What did PRIMECAP Management Co buy and sell last quarter?
Largest additions last quarterEst. value
Ownership stakes
Where is PRIMECAP Management Co a major shareholder?
By shares outstanding, PRIMECAP Management Co owns 12.8% of Xencor, Inc., 10.3% of Biogen Inc., 10.0% of Southwest Airlines Co. and 10.0% of MarketAxess Holdings Inc..
Reported value
How has PRIMECAP Management Co's 13F value moved?
Reported value went from $112.3B to $154.3B over 4 quarters. It moves with prices and with buying and selling, so it is not a fund return.
Latest 13F
What PRIMECAP Management Co changed in its latest 13F
| Company | Change | Shares vs prior | Est. value | Filed |
|---|---|---|---|---|
| Micron Technology, Inc. MU | -12% | $3.1B | Aug 14, 2026 | |
| KLA Corporation KLAC | -16% | $1.2B | Aug 14, 2026 | |
| Boston Scientific Corporation BSX | +55% | $767.9M | Aug 14, 2026 | |
| Amgen Inc. AMGN | -24% | $766.7M | Aug 14, 2026 | |
| Texas Instruments Incorporated TXN | -12% | $339.7M | Aug 14, 2026 | |
| Flex Ltd. FLEX | -8.0% | $328.1M | Aug 14, 2026 | |
| Illumina, Inc. ILMN | +70% | $254.5M | Aug 14, 2026 | |
| Space Exploration Technologies Corp. SPCX | New | $240.5M | Aug 14, 2026 | |
| Marsh MRSH | +199% | $237.9M | Aug 14, 2026 | |
| The Charles Schwab Corporation SCHW | +7.2% | $154.9M | Aug 14, 2026 | |
| The Goldman Sachs Group, Inc. GS | -99% | $154.2M | Aug 14, 2026 | |
| Carnival Corporation & plc CCL | New | $153.2M | Aug 14, 2026 | |
| Alphabet Inc. GOOG | -5.6% | $113.7M | Aug 14, 2026 | |
| Adobe Inc. ADBE | +10% | $101.7M | Aug 14, 2026 | |
| United Airlines Holdings, Inc. UAL | +4.5% | $96.7M | Aug 14, 2026 |
