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THERMO FISHER SCIENTIFIC INC

TMO

Holders

3

Combined Value

$921.17M

Combined Shares

1,874,089

Current Price

$469.34

52W High

$643.99

vs 52W High

−27.1%

Investor Activity Chart

Quarterly buys (▲) and sells (▼) by tracked investors. Click a marker to view that investor's portfolio; hover for details. Price line is implied from 13F filings (value ÷ shares), not market data.

$362.84$462.29$561.74$661.20Q2'24Q3'24Q4'24Q1'25Q2'25Q3'25Q4'25Q1'26Q2 2024 · implied price $553.00Q3 2024 · implied price $618.57Q4 2024 · implied price $520.23Q1 2025 · implied price $497.60Q2 2025 · implied price $405.46Q3 2025 · implied price $485.02Q4 2025 · implied price $579.45Q1 2026 · implied price $491.53Jim Simons - Renaissance Technologies · bought 235,849 shares @ ~$553.00 · Q2 2024 (new position)Tom Gayner - Markel Group · bought 29,400 shares @ ~$553.00 · Q2 2024 (new position)Tom Gayner - Markel Group · bought 6,000 shares @ ~$618.57 · Q3 2024Jim Simons - Renaissance Technologies · sold 186,898 shares @ ~$618.57 · Q3 2024Daniel Loeb - Third Point · bought 350,000 shares @ ~$520.23 · Q4 2024 (new position)Jim Simons - Renaissance Technologies · bought 132,393 shares @ ~$520.23 · Q4 2024Tom Gayner - Markel Group · bought 5,700 shares @ ~$520.23 · Q4 2024Tom Gayner - Markel Group · bought 3,900 shares @ ~$497.60 · Q1 2025Daniel Loeb - Third Point · sold 350,000 shares @ ~$520.23 · Q1 2025 (sold out)Jim Simons - Renaissance Technologies · sold 26,100 shares @ ~$497.60 · Q1 2025Jim Simons - Renaissance Technologies · bought 303,706 shares @ ~$405.46 · Q2 2025Stanley Druckenmiller - Duquesne Family Office · bought 12,200 shares @ ~$405.49 · Q2 2025 (new position)Tom Gayner - Markel Group · bought 4,550 shares @ ~$405.46 · Q2 2025Tom Gayner - Markel Group · bought 6,250 shares @ ~$485.02 · Q3 2025Harris Associates (Oakmark Funds) · bought 541 shares @ ~$485.02 · Q3 2025 (new position)Jim Simons - Renaissance Technologies · sold 458,950 shares @ ~$405.46 · Q3 2025 (sold out)Stanley Druckenmiller - Duquesne Family Office · sold 12,200 shares @ ~$405.49 · Q3 2025 (sold out)Andreas Halvorsen - Viking Global Investors · bought 874,838 shares @ ~$491.53 · Q1 2026Jim Simons - Renaissance Technologies · bought 138,964 shares @ ~$491.53 · Q1 2026 (new position)Tom Gayner - Markel Group · bought 4,300 shares @ ~$491.53 · Q1 2026Harris Associates (Oakmark Funds) · sold 541 shares @ ~$579.45 · Q1 2026 (sold out)Andreas Halvorsen - Viking Global Investors · bought 793,187 shares @ ~$579.45 · Q4 2025 (new position)Tom Gayner - Markel Group · bought 7,000 shares @ ~$579.45 · Q4 2025BUYSELLIMPLIED PRICE

Held By

Tracked investors currently holding this security, based on each investor's most recent 13F filing. Gain compares the current market price to each investor's estimated average buy price.

InvestorValue% of PortfolioAvg Buy PriceGainLast ActivityAs of
Andreas Halvorsen - Viking Global Investors$819.88M2.29%~$533.34−12.0%BUY Q1 2026Q1 2026
Jim Simons - Renaissance Technologies$68.30M0.11%~$491.53−4.5%BUY Q1 2026Q1 2026
Tom Gayner - Markel Group$32.98M0.28%~$535.34−12.3%BUY Q1 2026Q1 2026

Recent Activity

Latest position changes by tracked investors. Prices are estimates implied from 13F filings.

QuarterInvestorActionEst. ValueEst. Price
Q1 2026Andreas Halvorsen - Viking Global InvestorsBUY+$430.01M~$491.53
Q1 2026Jim Simons - Renaissance TechnologiesNEW BUY+$68.30M~$491.53
Q1 2026Tom Gayner - Markel GroupBUY+$2.11M~$491.53
Q1 2026Harris Associates (Oakmark Funds)SOLD OUT−$313.5K~$579.45
Q4 2025Andreas Halvorsen - Viking Global InvestorsNEW BUY+$459.61M~$579.45
Q4 2025Tom Gayner - Markel GroupBUY+$4.06M~$579.45
Q3 2025Jim Simons - Renaissance TechnologiesSOLD OUT−$186.09M~$405.46
Q3 2025Stanley Druckenmiller - Duquesne Family OfficeSOLD OUT−$4.95M~$405.49
Q3 2025Tom Gayner - Markel GroupBUY+$3.03M~$485.02
Q3 2025Harris Associates (Oakmark Funds)NEW BUY+$262.4K~$485.02
Q2 2025Jim Simons - Renaissance TechnologiesBUY+$123.14M~$405.46
Q2 2025Stanley Druckenmiller - Duquesne Family OfficeNEW BUY+$4.95M~$405.49
Q2 2025Tom Gayner - Markel GroupBUY+$1.84M~$405.46
Q1 2025Daniel Loeb - Third PointSOLD OUT−$182.08M~$520.23
Q1 2025Jim Simons - Renaissance TechnologiesSELL−$12.99M~$497.60
Q1 2025Tom Gayner - Markel GroupBUY+$1.94M~$497.60
Q4 2024Daniel Loeb - Third PointNEW BUY+$182.08M~$520.23
Q4 2024Jim Simons - Renaissance TechnologiesBUY+$68.87M~$520.23
Q4 2024Tom Gayner - Markel GroupBUY+$2.97M~$520.23
Q3 2024Jim Simons - Renaissance TechnologiesSELL−$115.61M~$618.57
Q3 2024Tom Gayner - Markel GroupBUY+$3.71M~$618.57
Q2 2024Jim Simons - Renaissance TechnologiesNEW BUY+$130.42M~$553.00
Q2 2024Tom Gayner - Markel GroupNEW BUY+$16.26M~$553.00

Ownership History

Aggregate position across all tracked investors per quarter (options excluded). Implied price is the reported value divided by shares held.

PeriodHoldersTotal SharesΔ SharesTotal ValueImplied Price
Q1 202631,874,089+118.8%$921.17M$491.53
Q4 20253856,528+1420.3%$496.32M$579.45
Q3 2025256,341-89.2%$27.33M$485.02
Q2 20253520,700+160.0%$211.12M$405.46
Q1 20252200,244-65.0%$99.64M$497.60
Q4 20243572,444+578.6%$297.80M$520.23
Q3 2024284,351-68.2%$52.18M$618.57
Q2 20242265,249—$146.68M$553.00