# Thermo Fisher Scientific, Inc. (TMO) — Institutional Ownership

Source: SEC EDGAR 13F filings, congressional STOCK Act disclosures, SEC Form 4 insider transactions.
CUSIP: 883556102
Page URL: https://superinvestorclub.com/stock/TMO
Last updated: 2026-08-29T13:48:23.503Z

## Summary

As of the most recent 13F filing period, Thermo Fisher Scientific, Inc. (TMO) is held by 18 tracked superinvestors with an aggregate position value of $3.89B representing 030547781937415817123769698514512248244165318115200731002766819200153971294867501241750652414 shares.

## Top institutional holders (18)

| Rank | Manager | Fund | Shares | Value | % of Portfolio | Period |
|------|---------|------|--------|-------|----------------|--------|
| 1 | [Dodge & Cox](https://superinvestorclub.com/manager/16) | Dodge & Cox | 3054778 | $1.53B | 0.80% | 2026-06-30 |
| 2 | [Andreas Halvorsen](https://superinvestorclub.com/manager/59) | Viking Global Investors | 1937415 | $971.3M | 2.77% | 2026-06-30 |
| 3 | [Dan Sundheim](https://superinvestorclub.com/manager/303) | D1 Capital Partners | 817123 | $409.7M | 1.18% | 2026-06-30 |
| 4 | [William Von Mueffling](https://superinvestorclub.com/manager/2284) | Cantillon Capital Management | 769698 | $378.3M | 2.51% | 2026-03-31 |
| 5 | [Lindsell Train](https://superinvestorclub.com/manager/68) | Lindsell Train | 514512 | $258.0M | 9.81% | 2026-06-30 |
| 6 | [Steven Romick](https://superinvestorclub.com/manager/289) | First Pacific Advisors | 248244 | $124.5M | 1.54% | 2026-06-30 |
| 7 | [Harry Burn](https://superinvestorclub.com/manager/81) | Sound Shore Management | 165318 | $82.9M | 2.55% | 2026-06-30 |
| 8 | [Wallace Weitz](https://superinvestorclub.com/manager/82) | Weitz Investment Management | 115200 | $57.8M | 4.00% | 2026-06-30 |
| 9 | [Tom Gayner](https://superinvestorclub.com/manager/22) | Markel Group | 73100 | $36.6M | 0.28% | 2026-06-30 |
| 10 | [David Katz](https://superinvestorclub.com/manager/79) | Matrix Asset Advisors | 27668 | $13.9M | 1.13% | 2026-06-30 |
| 11 | [Stanley Druckenmiller](https://superinvestorclub.com/manager/19) | Duquesne Family Office | 19200 | $9.6M | 0.18% | 2026-06-30 |
| 12 | [FPA Queens Road](https://superinvestorclub.com/manager/97) | Bragg Financial Advisors | 15397 | $7.7M | 0.21% | 2026-06-30 |
| 13 | [Ray Dalio](https://superinvestorclub.com/manager/6) | Bridgewater Associates | 12948 | $6.5M | 0.03% | 2026-06-30 |
| 14 | [Robert Olstein](https://superinvestorclub.com/manager/80) | Olstein Capital Management | 6750 | $3.3M | 0.72% | 2026-03-31 |
| 15 | [Mairs & Power](https://superinvestorclub.com/manager/92) | Mairs & Power | 1241 | $622,188 | 0.01% | 2026-06-30 |
| 16 | [Hillman Value Fund](https://superinvestorclub.com/manager/95) | Hillman Capital Management | 750 | $376,020 | 0.27% | 2026-06-30 |
| 17 | [Wally Obermeyer](https://superinvestorclub.com/manager/3283) | Obermeyer Wealth Partners | 652 | $326,887 | 0.01% | 2026-06-30 |
| 18 | [Dan Sundheim (Mine & Arao)](https://superinvestorclub.com/manager/3261) | Mine & Arao Wealth Creation & Management | 414 | $207,712 | 0.08% | 2026-06-30 |

## Ownership history (quarter-over-quarter)

- 2023-06-30: 2 holders, $1.5M aggregate, 015871202 shares
- 2023-09-30: 5 holders, $76.4M aggregate, 01250802223415871202783 shares
- 2023-12-31: 6 holders, $94.5M aggregate, 01250802717321967152112021108 shares
- 2024-03-31: 10 holders, $1.34B aggregate, 0151763946018312848912520026798247002101113071107749 shares
- 2024-06-30: 8 holders, $421.3M aggregate, 0524248125200337292940026791201891352863 shares
- 2024-09-30: 7 holders, $372.7M aggregate, 0423473120200354001975316651352683 shares
- 2024-12-31: 13 holders, $673.8M aggregate, 04072403500003137841202004110026121194561296016161200683414403 shares
- 2025-03-31: 14 holders, $2.14B aggregate, 023224829017735087903328451261504500026106157121349813061151683414403 shares
- 2025-06-30: 14 holders, $1.75B aggregate, 0219034887626585461215045087370495502642725941213771393712200800016161141 shares
- 2025-09-30: 15 holders, $1.11B aggregate, 086677081752921494615045011451355800257412151113759800016161129820541414 shares
- 2025-12-31: 18 holders, $1.68B aggregate, 087332279318768950321857213495062800500002574121341140626400230716861241718634541414 shares
- 2026-03-31: 16 holders, $2.10B aggregate, 01668025769698725005617211221896121000671002574122547146481448767501241695656414 shares

## Recent congressional trades (50)

- 2026-07-10: Dan Newhouse (Republican-WA) sale $1,001 - $15,000
- 2026-05-07: Dwight Evans (Democrat-PA) sale $1,001 - $15,000
- 2025-11-07: Ro Khanna (Democrat-CA) purchase $15,001 - $50,000
- 2025-10-31: Lisa McClain (Republican-MI) sale $1,001 - $15,000
- 2025-10-30: Lisa McClain (Republican-MI) sale $1,001 - $15,000
- 2025-10-30: Lisa McClain (Republican-MI) purchase $1,001 - $15,000
- 2025-09-23: Valerie Hoyle (D-OR) sale $1,001 - $15,000
- 2025-08-19: Kelly Morrison (Democrat-MN) sale $1,001 - $15,000
- 2025-08-19: Kelly Louise Morrison (D-MN) sale $15,001 - $50,000
- 2025-08-19: Kelly Louise Morrison (D-MN) sale $1,001 - $15,000
- 2025-08-19: Kelly Morrison (Democrat-MN) sale $15,001 - $50,000
- 2025-08-06: Ro Khanna (Democrat-CA) purchase $1,001 - $15,000
- 2025-08-04: Ro Khanna (Democrat-CA) purchase $15,001 - $50,000
- 2025-07-30: Ro Khanna (Democrat-CA) purchase $1,001 - $15,000
- 2025-07-25: Julia Letlow (Republican-LA) purchase $1,001 - $15,000

## Recent insider transactions (130)

- 2026-08-24: CASPER MARC N (Chairman & CEO) — Option Exercise 275 shares worth $85,148
- 2026-08-24: CASPER MARC N (Chairman & CEO) — Sell 62 shares
- 2026-08-24: CASPER MARC N (Chairman & CEO) — Sell 79 shares
- 2026-08-24: CASPER MARC N (Chairman & CEO) — Sell 33 shares
- 2026-08-24: CASPER MARC N (Chairman & CEO) — Sell 101 shares
- 2026-08-22: Meyer James (Sr. Vice President & CFO) — Tax Payment 30 shares worth $18,878
- 2026-08-21: CASPER MARC N (Chairman & CEO) — Sell 321 shares
- 2026-08-21: CASPER MARC N (Chairman & CEO) — Sell 2147 shares
- 2026-08-21: CASPER MARC N (Chairman & CEO) — Sell 1791 shares
- 2026-08-21: CASPER MARC N (Chairman & CEO) — Sell 3014 shares
- 2026-08-21: CASPER MARC N (Chairman & CEO) — Sell 2727 shares
- 2026-08-21: CASPER MARC N (Chairman & CEO) — Option Exercise 10000 shares worth $3.1M
- 2026-08-20: CASPER MARC N (Chairman & CEO) — Sell 2601 shares
- 2026-08-20: CASPER MARC N (Chairman & CEO) — Sell 1314 shares
- 2026-08-20: CASPER MARC N (Chairman & CEO) — Sell 821 shares

## Citation

When citing, use: "Thermo Fisher Scientific, Inc. (TMO) institutional ownership data via Superinvestor (https://superinvestorclub.com/stock/TMO), aggregating SEC 13F, Form 4, and congressional disclosures."