VIKING GLOBAL INVESTORS LP: THERMO FISHER SCIENTIFIC INC (TMO): Quarterly 13F Position History
As of Q2 2026, VIKING GLOBAL INVESTORS LP reported 1,937,415 shares of THERMO FISHER SCIENTIFIC INC (TMO), worth $971.3M and representing 2.8% of its 13F equity book. Quarter-over-quarter share count change: + 1,144,228 (+144.3%) . The position first appeared in Q4 2017 and has been disclosed across 34 13F-HR filings in Pactolio's tracked window.
- 1,937,415Shares Held (Latest Filing)
- $971.3MReported Market Value (Latest Filing)
- 2.8%Portfolio Weight (% of 13F Equity Book)
- +1,144,228Quarter-over-Quarter Share Change
- +$511.7MQuarter-over-Quarter Value Change
- 2,480,362Peak Reported Shares (Historical)
Quarterly 13F-HR Disclosure History Source: SEC 13F-HR filings, 34 quarter s
| Quarter | Shares | QoQ Share Change | Share Change (%) | Market Value | Weight | Implied Price |
|---|---|---|---|---|---|---|
| Q2 2026 | 1,937,415 | +1,144,228 | +144.3% | $971.3M | 2.8% | $501.4 |
| Q4 2025 | 793,187 | +793,187 | – | $459.6M | 1.2% | $579.5 |
| Q3 2025 | 0 | 0 | – | $0 | 0.0% | – |
| Q2 2025 | 0 | 0 | – | $0 | 0.0% | – |
| Q1 2025 | 0 | 0 | – | $0 | 0.0% | – |
| Q4 2024 | 0 | 0 | – | $0 | 0.0% | – |
| Q3 2024 | 0 | 0 | – | $0 | 0.0% | – |
| Q2 2024 | 0 | 128,489 | -100.0% | $0 | 0.0% | – |
| Q1 2024 | 128,489 | 409,996 | -76.1% | $74.7M | 0.3% | $581.2 |
| Q4 2023 | 538,485 | 361,230 | -40.1% | $285.8M | 1.0% | $530.8 |
| Q3 2023 | 899,715 | +66,482 | +8.0% | $455.4M | 1.8% | $506.2 |
| Q2 2023 | 833,233 | 23,603 | -2.8% | $434.7M | 1.8% | $521.8 |
| Q1 2023 | 856,836 | +17,310 | +2.1% | $493.9M | 2.3% | $576.4 |
| Q4 2022 | 839,526 | +245,989 | +41.4% | $462.3M | 2.3% | $550.7 |
| Q3 2022 | 593,537 | 269,050 | -31.2% | $301.0M | 1.4% | $507.2 |
| Q2 2022 | 862,587 | +377,891 | +78.0% | $468.6M | 2.1% | $543.3 |
| Q1 2022 | 484,696 | +273,638 | +129.7% | $286.3M | 1.2% | $590.7 |
| Q4 2021 | 211,058 | +28,821 | +15.8% | $140.8M | 0.4% | $667.2 |
| Q3 2021 | 182,237 | 829,164 | -82.0% | $104.1M | 0.3% | $571.3 |
| Q2 2021 | 1,011,401 | +149,514 | +17.3% | $510.2M | 1.5% | $504.5 |
| Q1 2021 | 861,887 | +784,070 | +1007.6% | $393.3M | 1.2% | $456.4 |
| Q4 2020 | 77,817 | 1,299,406 | -94.3% | $36.2M | 0.1% | $465.8 |
| Q3 2020 | 1,377,223 | 356,921 | -20.6% | $608.1M | 2.2% | $441.5 |
| Q2 2020 | 1,734,144 | +1,734,144 | – | $628.4M | 2.7% | $362.3 |
| Q1 2020 | 0 | 0 | – | $0 | 0.0% | – |
| Q4 2019 | 0 | 0 | – | $0 | 0.0% | – |
| Q3 2019 | 0 | 0 | – | $0 | 0.0% | – |
| Q2 2019 | 0 | 1,146,037 | -100.0% | $0 | 0.0% | – |
| Q1 2019 | 1,146,037 | +598,131 | +109.2% | $313.7M | 1.8% | $273.7 |
| Q4 2018 | 547,906 | 1,329,914 | -70.8% | $122.6M | 0.7% | $223.8 |
| Q3 2018 | 1,877,820 | 602,542 | -24.3% | $458.3M | 2.5% | $244.1 |
| Q2 2018 | 2,480,362 | +1,615,681 | +186.9% | $513.8M | 2.9% | $207.1 |
| Q1 2018 | 864,681 | +50,164 | +6.2% | $178.5M | 1.1% | $206.5 |
| Q4 2017 | 814,517 | – | – | $154.7M | 1.0% | $189.9 |
Methodology & FAQ
How This Position History Is Sourced
Each row is one SEC Form 13F-HR filing disclosing this position. Share count, market value, and reported quarter are taken verbatim from the filing; portfolio weight is recomputed against the same filing's total reported equity book. Implied price-per-share is market value divided by shares, a quarter-end mark rather than the manager's cost basis. See the full methodology document for the normalization rules.
When did VIKING GLOBAL INVESTORS LP first disclose a TMO position in 13F-HR filings?
VIKING GLOBAL INVESTORS LP first reported THERMO FISHER SCIENTIFIC INC (TMO) on its 13F-HR filing for the period ending 2017-12-31 (Q4 2017). The position has appeared on 34 reported quarters within Pactolio's tracked window.
What was VIKING GLOBAL INVESTORS LP's most recent quarter-over-quarter share-count change in TMO?
Between Q4 2025 and Q2 2026, VIKING GLOBAL INVESTORS LP added 1,144,228 shares of TMO (+144.3%), bringing the total reported position to 1,937,415 shares at a market value of $971.3M.
Does the implied price-per-share represent VIKING GLOBAL INVESTORS LP's cost basis in TMO?
No. The implied price-per-share column is the 13F-HR reported market value divided by reported share count on the filing date (end of quarter). It is a quarter-end mark, not a cost basis or transaction price. Use it as a sanity check on the value column, not as an indicator of the manager's entry or exit price.