Thermo Fisher Scientific Inc.
MX ˙ BMV ˙ US8835561023
SecurityMX:TMO / Thermo Fisher Scientific Inc.
InstitutionLongview Partners (Guernsey) LTD
Latest Disclosed Ownership662,828 shares
Latest Disclosed Value $ 325,799,847
Longview Partners (Guernsey) LTD reports 22.05% decrease in ownership of TMO / Thermo Fisher Scientific Inc.

On May 15, 2026 - Longview Partners (Guernsey) LTD filed a 13F-HR form disclosing ownership of 662,828 shares of Thermo Fisher Scientific Inc. (MX:TMO) valued at $325,799,847 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 850,276 shares of Thermo Fisher Scientific Inc.. This represents a change in shares of -22.05% during the quarter.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-15 2026-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 662,828 -187,448 -22.05 325,800 -33.87 4.6160
2026-02-17 2025-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 850,276 -53,290 -5.90 492,692 12.42 5.1451
2025-11-13 2025-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 903,566 34,981 4.03 438,248 24.44 4.5802
2025-08-13 2025-06-30 13F THERMO FISHER SCIENTIFIC COM 883556102 868,585 -45,600 -4.99 352,176 -22.58 3.0344
2025-05-14 2025-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 914,185 -56,619 -5.83 454,898 -9.93 3.6602
2025-02-13 2024-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 970,804 -41,263 -4.08 505,041 -19.33 3.7715
2024-11-13 2024-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 1,012,067 8,338 0.83 626,034 12.79 4.2944
2024-08-13 2024-06-30 13F THERMO FISHER SCIENTIFIC COM 883556102 1,003,729 -135,390 -11.89 555,062 -16.16 4.1185
2024-05-14 2024-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 1,139,119 -32,590 -2.78 662,067 6.45 4.2752
2024-02-13 2023-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 1,171,709 1,171,709 621,931 4.1490
2019-05-14 2019-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 0 -1,484,698 -100.00 0 -100.00
2019-02-13 2018-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 1,484,698 -28,365 -1.87 332,261 -10.03 1.7683
2018-10-19 2018-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 1,513,063 -1,706,592 -53.01 369,308 -44.62 1.8231
2018-08-01 2018-06-30 13F THERMO FISHER SCIENTIFIC COM 883556102 3,219,655 -190,875 -5.60 666,919 -5.29 3.4732
2018-04-16 2018-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 3,410,530 -1,466,360 -30.07 704,138 -23.96 3.6911
2018-02-06 2017-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 4,876,890 311,977 6.83 926,024 7.22 4.8483
2017-10-30 2017-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 4,564,913 313,782 7.38 863,682 16.45 4.6652
2017-07-26 2017-06-30 13F THERMO FISHER SCIENTIFIC COM 883556102 4,251,131 84,180 2.02 741,695 15.88 4.2772
2017-05-08 2017-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 4,166,951 -200,575 -4.59 640,044 3.86 4.1627
2017-02-10 2016-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 4,367,526 -186,213 -4.09 616,258 -14.92 4.0722
2016-11-07 2016-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 4,553,739 -376,823 -7.64 724,318 -0.58 4.6902
2016-07-29 2016-06-30 13F THERMO FISHER SCIENTIFIC COM 883556102 4,930,562 -125,708 -2.49 728,540 1.76 4.8487
2016-04-20 2016-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 5,056,270 -123,096 -2.38 715,917 -2.56 4.7603
2016-01-29 2015-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 5,179,366 54,191 1.06 734,693 17.23 5.0104
2015-11-02 2015-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 5,125,175 5,125,175 626,706 4.4280
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.