MERCK & CO. INC. (MRK) Stock Institutional Trading Activity


MERCK & CO. INC. (MRK) 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 Causeway Capital Management, Cullen Value Fund, Kahn Brothers Group, Matrix Private Capital Group, and Mairs & Power Growth Fund. 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
Q2 2020Renaissance Technologies LLCSell-3,151,9413,740,429$289,247
Q2 2020Gardner Russo & QuinnBuy1,1753,926$304
Q1 2020Torray FundSell-4,58516,724$1,287
Q1 2020Dodge & Cox Stock FundSell-172,438516,958$39,775
Q1 2020Sound Shore ManagementBuy107,1941,674,297$128,820
Q1 2020Causeway Capital ManagementSell-315,0681,455,042$111,951
Q1 2020Matrix Private Capital GroupSell-1,0007,992$620
Q1 2020Sequoia Financial AdvisorsBuy4,17432,856$2,528
Q1 2020Hillman Value FundBuy3,06338,522$2,964
Q1 2020Semper Augustus Investments GroupBuy1,53244,044$3,389
Q1 2020Mairs & Power Growth FundSell-87481,654$6,282
Q1 2020Matrix Advisors Value FundBuy16,739118,009$9,080
Q1 2020Renaissance Technologies LLCBuy1,219,1276,892,370$530,299
Q1 2020Hancock Classic ValueSell-33,21325,598$1,970
Q4 2019Torray FundSell-24521,309$1,938
Q4 2019Mairs & Power Growth FundBuy2,06382,528$7,506
Q4 2019Dodge & Cox Stock FundSell-11,947689,396$62,701
Q4 2019Sound Shore ManagementSell-111,8571,567,103$142,528
Q4 2019Matrix Private Capital GroupBuy8,9928,992$823
Q4 2019Sequoia Financial AdvisorsBuy1,37428,682$2,609
Q4 2019Hillman Value FundBuy17,65235,459$3,225
Q4 2019Hancock Classic ValueSell-710,61158,811$5,349
Q4 2019Matrix Advisors Value FundBuy1,216101,270$9,211
Q4 2019Causeway Capital ManagementSell-59,4751,770,110$160,992
Q4 2019Renaissance Technologies LLCBuy1,625,8305,673,243$515,981
Q4 2019Gardner Russo & QuinnSell-302,751$250
Q3 2019Torray FundBuy19521,554$1,814
Q3 2019Mairs & Power Growth FundBuy2,06080,465$6,774
Q3 2019Dodge & Cox Stock FundSell-13,279701,343$59,039
Q3 2019Sound Shore ManagementSell-33,4661,678,960$141,335

Frequently asked questions about MRK activity

  • Which institutional owners are buying MRK?

    Institutional owners buying MRK 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 MRK activity?

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

  • Is institutional interest in MRK increasing?

    Institutional interest in MRK 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.