PACIFIC BIOSCIENCES OF CALIF (PACB) Institutional Ownership Changes & 13F Activity

PACIFIC BIOSCIENCES OF CALIF (PACB) institutional ownership data tracks hedge funds, asset managers, and other institutional investors based on recent SEC 13F filings (Q1 2026). This page analyzes institutional buying and selling activity, new holdings, and sold-out positions among tracked filers. Notable filers include Renaissance Technologies LLC, ARK Invest, Polen Capital Management, Viking Global Investors, and Fairfax Financial Holdings.

Portfolio quarterNameTypeQuantityRemainingReported stock balance
Q1 2021Viking Global InvestorsSell-1,269,580293,335$9,771
Q1 2021Renaissance Technologies LLCBuy669,600783,500$26,098
Q4 2020ARK InvestBuy8,659,84928,504,629$739,410
Q4 2020Viking Global InvestorsSell-2,955,7081,562,915$40,542
Q3 2020ARK InvestBuy11,613,28819,844,780$195,868
Q3 2020Viking Global InvestorsBuy4,518,6234,518,623$44,599
Q2 2020ARK InvestBuy4,038,4338,231,492$28,399
Q1 2020ARK InvestBuy2,683,6454,193,059$12,831
Q4 2019ARK InvestBuy752,6171,509,414$7,758
Q3 2019ARK InvestBuy756,797756,797$3,905
Q2 2019ARK InvestSell-5900$0
Q4 2018ARK InvestSell-7,785,895590$4
Q4 2018Fairfax Financial HoldingsBuy160,000160,000$1,182
Q3 2018ARK InvestBuy1,465,1927,786,485$42,125
Q2 2018ARK InvestBuy2,036,5966,321,293$22,441
Q1 2018ARK InvestBuy4,070,7804,284,697$8,784
Q4 2017Renaissance Technologies LLCSell-261,000113,900$301
Q4 2017ARK InvestBuy179,192213,917$565
Q3 2017ARK InvestBuy34,72534,725$182
Q3 2016Renaissance Technologies LLCSell-29,164374,900$3,359
Q2 2016Renaissance Technologies LLCSell-784,636404,064$2,843
Q1 2016Renaissance Technologies LLCSell-397,7001,188,700$10,104
Q4 2015Renaissance Technologies LLCBuy1,276,9001,586,400$20,829
Q3 2015Muhlenkamp & CoBuy11,12511,125$41
Q2 2015Renaissance Technologies LLCBuy184,300309,500$1,783
Q1 2015Renaissance Technologies LLCSell-12,772125,200$731
Q4 2014Renaissance Technologies LLCBuy32,206137,972$1,082
Q1 2014Renaissance Technologies LLCSell-174,334105,766$566
Q3 2013Renaissance Technologies LLCBuy4,100280,100$1,546
Q2 2013Renaissance Technologies LLCBuy276,000276,000$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.

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