INSPIRE MEDICAL SYSTEMS INC (INSP) Institutional Ownership Changes & 13F Activity

INSPIRE MEDICAL SYSTEMS INC (INSP) 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, Mairs & Power Growth Fund, and Viking Global Investors.

Portfolio quarterNameTypeQuantityRemainingReported stock balance
Q3 2022Renaissance Technologies LLCSell-21,20016,500$2,927
Q3 2022Mairs & Power Growth FundBuy256132,007$23,414
Q2 2022Viking Global InvestorsBuy284,312595,193$108,724
Q2 2022Mairs & Power Growth FundSell-688131,751$24,067
Q1 2022Viking Global InvestorsBuy310,881310,881$79,800
Q1 2022Mairs & Power Growth FundSell-38,644132,439$33,996
Q1 2022Renaissance Technologies LLCBuy6,60037,700$9,677
Q4 2021Renaissance Technologies LLCSell-12,33931,100$7,155
Q4 2021Mairs & Power Growth FundSell-1,120171,083$39,359
Q3 2021Mairs & Power Growth FundSell-5,531172,203$40,103
Q2 2021Mairs & Power Growth FundBuy101,355177,734$34,349
Q2 2021Renaissance Technologies LLCSell-66,26143,439$8,395
Q1 2021Mairs & Power Growth FundSell-6,30676,379$15,810
Q4 2020Renaissance Technologies LLCBuy23,600109,700$20,633
Q3 2020Renaissance Technologies LLCSell-77,50086,100$11,111
Q3 2020Mairs & Power Growth FundSell-21,94082,685$10,670
Q2 2020Renaissance Technologies LLCSell-113,700163,600$14,236
Q2 2020Mairs & Power Growth FundSell-48,085104,625$9,104
Q1 2020Renaissance Technologies LLCBuy201,000277,300$16,716
Q1 2020Mairs & Power Growth FundSell-4,555152,710$9,205
Q4 2019Renaissance Technologies LLCSell-4,10076,300$5,662
Q4 2019Mairs & Power Growth FundBuy50157,265$11,671
Q3 2019Mairs & Power Growth FundBuy405157,215$9,593
Q3 2019Renaissance Technologies LLCSell-40080,400$4,906
Q2 2019Renaissance Technologies LLCBuy80,80080,800$4,901
Q2 2019Mairs & Power Growth FundBuy80156,810$9,511
Q1 2019Mairs & Power Growth FundBuy165156,730$8,899
Q4 2018Mairs & Power Growth FundBuy28,365156,565$6,615
Q3 2018Mairs & Power Growth FundBuy10,100128,200$5,395
Q2 2018Mairs & Power Growth FundBuy118,100118,100$4,211

Frequently asked questions about INSP activity

  • Which institutional owners are buying INSP?

    Institutional owners buying INSP 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 INSP activity?

    "Buy" means an investor increased their reported position in INSP compared to the prior reporting period. This reflects growing exposure to INSPIRE MEDICAL SYSTEMS INC (INSP) rather than necessarily a brand-new position (though new positions also appear as buys when prior quantity was zero).

  • Is institutional interest in INSP increasing?

    Institutional interest in INSP 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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