PACIFIC BIOSCIENCES OF CALIF (PACB) Stock Institutional Trading Activity
PACIFIC BIOSCIENCES OF CALIF (PACB) position changes reported by tracked institutional filers across multiple SEC 13F reporting periods. Based on recent SEC 13F filings (Q4 2025), investors with some of the largest reported share count changes include Renaissance Technologies LLC, Polen Capital Management, ARK Invest, Viking Global Investors, and Fairfax Financial Holdings. Explore insights into buying and selling patterns, position changes, and investment conviction levels to understand institutional trading behavior and market dynamics.
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- PACIFIC BIOSCIENCES OF CALIF (PACB) stock institutional ownership
- PACIFIC BIOSCIENCES OF CALIF (PACB) stock insider trading activity
- Stock rankings
| Portfolio quarter | Name | Type | Quantity | Remaining | Reported stock balance |
|---|---|---|---|---|---|
| Q4 2020 | ARK Invest | Buy | 8,659,849 | 28,504,629 | $739,410 |
| Q3 2020 | Viking Global Investors | Buy | 4,518,623 | 4,518,623 | $44,599 |
| Q3 2020 | ARK Invest | Buy | 11,613,288 | 19,844,780 | $195,868 |
| Q2 2020 | ARK Invest | Buy | 4,038,433 | 8,231,492 | $28,399 |
| Q1 2020 | ARK Invest | Buy | 2,683,645 | 4,193,059 | $12,831 |
| Q4 2019 | ARK Invest | Buy | 752,617 | 1,509,414 | $7,758 |
| Q3 2019 | ARK Invest | Buy | 756,797 | 756,797 | $3,905 |
| Q2 2019 | ARK Invest | Sell | -590 | 0 | $0 |
| Q4 2018 | Fairfax Financial Holdings | Buy | 160,000 | 160,000 | $1,182 |
| Q4 2018 | ARK Invest | Sell | -7,785,895 | 590 | $4 |
| Q3 2018 | ARK Invest | Buy | 1,465,192 | 7,786,485 | $42,125 |
| Q2 2018 | ARK Invest | Buy | 2,036,596 | 6,321,293 | $22,441 |
| Q1 2018 | ARK Invest | Buy | 4,070,780 | 4,284,697 | $8,784 |
| Q4 2017 | Renaissance Technologies LLC | Sell | -261,000 | 113,900 | $301 |
| Q4 2017 | ARK Invest | Buy | 179,192 | 213,917 | $565 |
| Q3 2017 | ARK Invest | Buy | 34,725 | 34,725 | $182 |
| Q3 2016 | Renaissance Technologies LLC | Sell | -29,164 | 374,900 | $3,359 |
| Q2 2016 | Renaissance Technologies LLC | Sell | -784,636 | 404,064 | $2,843 |
| Q1 2016 | Renaissance Technologies LLC | Sell | -397,700 | 1,188,700 | $10,104 |
| Q4 2015 | Renaissance Technologies LLC | Buy | 1,276,900 | 1,586,400 | $20,829 |
| Q3 2015 | Muhlenkamp & Co | Buy | 11,125 | 11,125 | $41 |
| Q2 2015 | Renaissance Technologies LLC | Buy | 184,300 | 309,500 | $1,783 |
| Q1 2015 | Renaissance Technologies LLC | Sell | -12,772 | 125,200 | $731 |
| Q4 2014 | Renaissance Technologies LLC | Buy | 32,206 | 137,972 | $1,082 |
| Q1 2014 | Renaissance Technologies LLC | Sell | -174,334 | 105,766 | $566 |
| Q3 2013 | Renaissance Technologies LLC | Buy | 4,100 | 280,100 | $1,546 |
| Q2 2013 | Renaissance Technologies LLC | Buy | 276,000 | 276,000 | $698 |
Frequently asked questions about PACB activity
Which institutional owners are buying PACB?
Institutional owners buying PACB include investors who have either initiated new positions or increased their existing holdings based on recent SEC 13F filings. The activity table above highlights which funds added shares in the latest reporting periods and how their positions changed over time.
What does "buy" mean in PACB activity?
"Buy" means an investor increased their reported position in PACB compared to the prior reporting period. This reflects growing exposure to PACIFIC BIOSCIENCES OF CALIF (PACB) rather than necessarily a brand-new position (though new positions also appear as buys when prior quantity was zero).
Is institutional interest in PACB increasing?
Institutional interest in PACB can be assessed by comparing the number of tracked funds adding or increasing positions versus those trimming or exiting across the periods shown. A higher number of additions typically signals increasing participation among large filers, but it should be read alongside position sizes and the full table.