IRIDIUM COMMUNICATIONS INC (IRDM) Stock Institutional Trading Activity


IRIDIUM COMMUNICATIONS INC (IRDM) 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 Cullen Value Fund, ARK Invest, and Renaissance Technologies LLC. 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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Portfolio quarterNameTypeQuantityRemainingReported stock balance
Q4 2017Renaissance Technologies LLCBuy33,100247,799$2,924
Q3 2017Renaissance Technologies LLCBuy111,600214,699$2,211
Q2 2017Renaissance Technologies LLCSell-53,501103,099$1,139
Q3 2016Renaissance Technologies LLCBuy93,900156,600$1,270
Q2 2016Renaissance Technologies LLCSell-115,69962,700$557
Q3 2015Renaissance Technologies LLCBuy110,299178,399$1,097
Q1 2015Renaissance Technologies LLCSell-132,69968,100$661
Q4 2014Renaissance Technologies LLCSell-47,900200,799$1,958
Q3 2014Renaissance Technologies LLCBuy131,000248,699$2,201
Q2 2014Renaissance Technologies LLCBuy45,050117,699$996
Q4 2013Renaissance Technologies LLCSell-45,60072,649$454
Q2 2013Renaissance Technologies LLCBuy118,249118,249$918

Frequently asked questions about IRDM activity

  • Which institutional owners are buying IRDM?

    Institutional owners buying IRDM 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 IRDM activity?

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

  • Is institutional interest in IRDM increasing?

    Institutional interest in IRDM 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.