Thermo Fisher Scientific Inc.
MX ˙ BMV ˙ US8835561023
SecurityMX:TMO / Thermo Fisher Scientific Inc.
InstitutionRobeco Institutional Asset Management B.V.
Latest Disclosed Ownership634,639 shares
Latest Disclosed Value $ 311,944,106
Robeco Institutional Asset Management B.V. reports 23.16% decrease in ownership of TMO / Thermo Fisher Scientific Inc.

On April 21, 2026 - Robeco Institutional Asset Management B.V. filed a 13F-HR form disclosing ownership of 634,639 shares of Thermo Fisher Scientific Inc. (MX:TMO) valued at $311,944,106 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 23, 2026 disclosing 825,966 shares of Thermo Fisher Scientific Inc.. This represents a change in shares of -23.16% 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)
2026-04-21 2026-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 634,639 -191,327 -23.16 311,944 -34.82 0.4446
2026-01-23 2025-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 825,966 66,890 8.81 478,606 30.00 0.6816
2025-10-22 2025-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 759,076 233,200 44.35 368,167 72.67 0.5333
2025-07-18 2025-06-30 13F THERMO FISHER SCIENTIFIC COM 883556102 525,876 -165,731 -23.96 213,222 -38.04 0.3448
2025-04-23 2025-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 691,607 86,494 14.29 344,144 9.32 0.6685
2025-01-23 2024-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 605,113 30,758 5.36 314,798 -11.39 0.5967
2024-10-29 2024-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 574,355 16,561 2.97 355,279 15.18 0.7057
2024-07-23 2024-06-30 13F THERMO FISHER SCIENTIFIC COM 883556102 557,794 -68,289 -10.91 308,460 -15.23 0.6637
2024-04-24 2024-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 626,083 75,792 13.77 363,886 24.58 0.7907
2024-02-14 2023-12-31 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 550,291 111,504 25.41 292,089 31.51 0.7081
2024-02-08 2023-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 440,404 1,617 550 0.1031
2023-10-24 2023-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 438,787 -37,425 -7.86 222,101 -10.61 0.5935
2023-07-24 2023-06-30 13F THERMO FISHER SCIENTIFIC COM 883556102 476,212 -93,998 -16.48 248,464 -24.40 0.6514
2023-05-04 2023-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 570,210 147,636 34.94 328,652 41.23 0.8959
2023-02-07 2022-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 422,574 2,298 0.55 232,707 9.17 0.6706
2022-12-01 2022-09-30 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 420,276 20,138 5.03 213,161 -1.94 0.6888
2022-10-27 2022-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 426,094 20,514 216,112 0.6890
2022-12-01 2022-06-30 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 400,138 -226,892 -36.19 217,385 -41.30 0.6754
2022-07-27 2022-06-30 13F THERMO FISHER SCIENTIFIC COM 883556102 405,580 -221,450 220,342 0.6750
2022-12-01 2022-03-31 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 627,030 -73,346 -10.47 370,355 -20.75 0.8724
2022-04-26 2022-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 627,030 -73,346 370,355 0.8619
2022-12-01 2021-12-31 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 700,376 -84,960 -10.82 467,318 4.15 0.9946
2022-01-31 2021-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 700,376 -84,960 467,318 0.9822
2022-12-01 2021-09-30 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 785,336 -37,330 -4.54 448,688 8.11 0.9948
2021-10-20 2021-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 785,336 -37,330 448,688 0.9821
2022-12-01 2021-06-30 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 822,666 -53,680 -6.13 415,011 3.77 0.9200
2021-07-28 2021-06-30 13F THERMO FISHER SCIENTIFIC COM 883556102 822,666 -53,680 415,011 0.9074
2022-12-01 2021-03-31 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 876,346 265,409 43.44 399,948 40.55 0.9857
2021-04-23 2021-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 876,346 265,409 399,948 0.9719
2022-12-01 2020-12-31 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 610,937 300,081 96.53 284,560 107.33 0.7477
2021-01-28 2020-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 610,937 300,081 284,560 0.7387
2021-01-19 2020-09-30 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 310,856 111,210 55.70 137,251 89.73 0.4242
2020-10-29 2020-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 310,856 111,210 137,251 423,875.7577
2021-01-19 2020-06-30 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 199,646 -3,155 -1.56 72,340 25.78 0.2457
2020-07-20 2020-06-30 13F THERMO FISHER SCIENTIFIC COM 883556102 199,646 -3,155 72,340 245,462.5231
2021-01-19 2020-03-31 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 202,801 5,501 2.79 57,512 -10.28 0.2307
2020-04-30 2020-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 202,801 5,501 57,512 230,521.0661
2021-01-19 2019-12-31 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 197,300 8,584 4.55 64,102 16.62 0.2052
2020-02-06 2019-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 197,300 8,584 64,102 205,025.3176
2021-01-19 2019-09-30 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 188,716 -12,377 -6.15 54,967 -6.93 0.1941
2019-10-17 2019-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 188,716 -12,377 54,967 193,781.2803
2021-01-19 2019-06-30 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 201,093 37,561 22.97 59,057 31.94 0.2086
2019-07-19 2019-06-30 13F THERMO FISHER SCIENTIFIC COM 883556102 201,093 37,561 59,057 208,250.4295
2021-01-19 2019-03-31 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 163,532 13,966 9.34 44,760 33.76 0.1646
2019-05-02 2019-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 163,532 13,966 44,760 164,342.7973
2021-01-19 2018-12-31 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 149,566 26,566 21.60 33,463 11.46 0.1503
2019-02-08 2018-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 149,566 26,566 33,463 149,996.2392
2021-01-19 2018-09-30 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 123,000 -2,452 -1.95 30,022 15.52 0.1189
2018-10-25 2018-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 122,652 -2,800 29,937
2021-01-19 2018-06-30 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 125,452 -22,611 -15.27 25,989 -14.98 0.1184
2018-08-03 2018-06-30 13F THERMO FISHER SCIENTIFIC COM 883556102 125,452 -22,611 25,989
2021-01-19 2018-03-31 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 148,063 61,316 70.68 30,569 85.56 0.1434
2018-05-07 2018-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 148,063 61,316 30,569 142,956.9133
2021-01-19 2017-12-31 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 86,747 4,647 5.66 16,474 6.04 0.0854
2018-01-25 2017-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 86,747 4,647 16,474
2021-01-19 2017-09-30 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 82,100 -3,032 -3.56 15,535 4.61 0.0965
2017-10-17 2017-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 82,100 -3,032 15,535 96,244.7748
2021-01-19 2017-06-30 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 85,132 5,668 7.13 14,851 21.69 0.0957
2017-08-07 2017-06-30 13F THERMO FISHER SCIENTIFIC COM 883556102 85,132 5,668 14,851 96,691.9705
2021-01-19 2017-03-31 13F/A-1 THERMO FISHER SCIENTIFIC COM 883556102 79,464 -57,850 -42.13 12,204 -37.01 0.0813
2017-05-15 2017-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 79,464 -57,850 12,204 81,058.2310
2017-02-09 2016-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 137,314 -27,887 -16.88 19,374 -26.27 0.1516
2016-11-07 2016-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 165,201 8,726 5.58 26,277 13.65 0.1942
2016-07-22 2016-06-30 13F THERMO FISHER SCIENTIFIC COM 883556102 156,475 1,538 0.99 23,122 5.40 0.1753
2016-05-16 2016-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 154,937 -16,350 -9.55 21,938 -9.71 0.1760
2016-02-08 2015-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 171,287 -6,569 -3.69 24,297 11.72 0.2078
2015-11-12 2015-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 177,856 31,839 21.80 21,748 14.78 0.1657
2015-08-17 2015-06-30 13F THERMO FISHER SCIENTIFIC COM 883556102 146,017 29,175 24.97 18,947 20.70 0.1438
2015-04-24 2015-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 116,842 -4,092 -3.38 15,697 3.60 0.1180
2015-02-12 2014-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 120,934 -83,267 -40.78 15,152 -39.03 0.1086
2014-11-10 2014-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 204,201 -2,784 -1.35 24,853 1.76 0.1775
2014-08-13 2014-06-30 13F THERMO FISHER SCIENTIFIC COM 883556102 206,985 675 0.33 24,422 -1.56 0.1748
2014-05-07 2014-03-31 13F THERMO FISHER SCIENTIFIC COM 883556102 206,310 -39,566 -16.09 24,808 -9.39 0.1903
2014-02-04 2013-12-31 13F THERMO FISHER SCIENTIFIC COM 883556102 245,876 66,514 37.08 27,379 65.65 0.2275
2013-11-12 2013-09-30 13F THERMO FISHER SCIENTIFIC COM 883556102 179,362 130,312 265.67 16,528 298.17 0.1606
2013-08-27 2013-06-30 13F Thermo Fisher Scientific COM 883556102 49,050 49,050 4,151 0.0420
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.