VOL. XCIV, NO. 247

★ WIDE MOAT STOCKS COMPARISON ★

NO ADVICE

Wednesday, December 31, 2025

Stock Comparison

Marsh & McLennan Companies, Inc. vs Thermo Fisher Scientific Inc.

Compare moat strength, market structure, and segment coverage to understand how each company defends its edge.

Marsh & McLennan Companies, Inc.

MMC · New York Stock Exchange

Market cap (USD)
SectorFinancials
CountryUS
Data as of2025-12-31
Moat score
65/ 100

Weighted average of segment moat scores, combining moat strength, durability, confidence, market structure, pricing power, and market share.

Full stock profile

Dive deeper into Marsh & McLennan Companies, Inc.'s moat claims, evidence, and risks.

View MMC analysis

Thermo Fisher Scientific Inc.

TMO · New York Stock Exchange

Market cap (USD)$213.3B
SectorHealthcare
CountryUS
Data as of2025-12-22
Moat score
64/ 100

Weighted average of segment moat scores, combining moat strength, durability, confidence, market structure, pricing power, and market share.

Full stock profile

Dive deeper into Thermo Fisher Scientific Inc.'s moat claims, evidence, and risks.

View TMO analysis

Comparison highlights

  • Moat score gap: Marsh & McLennan Companies, Inc. leads (65 / 100 vs 64 / 100 for Thermo Fisher Scientific Inc.).
  • Segment focus: Marsh & McLennan Companies, Inc. has 2 segments (62.8% in Risk and Insurance Services); Thermo Fisher Scientific Inc. has 4 segments (53.6% in Laboratory Products and Biopharma Services).
  • Primary market structure: Oligopoly vs Competitive. Pricing power: Moderate vs Moderate.
  • Moat breadth: Marsh & McLennan Companies, Inc. has 5 moat types across 3 domains; Thermo Fisher Scientific Inc. has 8 across 3.

Primary market context

Marsh & McLennan Companies, Inc.

Risk and Insurance Services

Market

Insurance brokerage, risk advisory, and reinsurance brokerage/services

Geography

Global

Customer

Enterprises, public entities, associations, and individuals (via broker/agent channels)

Role

Intermediary + advisor (insurance/reinsurance market intermediary)

Revenue share

62.8%

Thermo Fisher Scientific Inc.

Laboratory Products and Biopharma Services

Market

Laboratory supplies distribution/market channel plus outsourced biopharma services (CDMO/CRO)

Geography

Global

Customer

Pharma & biotech; academic/government labs; industrial and clinical laboratories

Role

Distributor/market channel and outsourced services provider

Revenue share

53.6%

Side-by-side metrics

Marsh & McLennan Companies, Inc.
Thermo Fisher Scientific Inc.
Ticker / Exchange
MMC - New York Stock Exchange
TMO - New York Stock Exchange
Market cap (USD)
n/a
$213.3B
Sector
Financials
Healthcare
HQ country
US
US
Primary segment
Risk and Insurance Services
Laboratory Products and Biopharma Services
Market structure
Oligopoly
Competitive
Market share
n/a
n/a
HHI estimate
n/a
n/a
Pricing power
Moderate
Moderate
Moat score
65 / 100
64 / 100
Moat domains
Supply, Demand, Legal
Demand, Supply, Legal
Last update
2025-12-31
2025-12-22

Moat coverage

Shared moat types

Service Field NetworkBrand Trust

Marsh & McLennan Companies, Inc. strengths

Switching Costs GeneralCompliance AdvantageData Workflow Lockin

Thermo Fisher Scientific Inc. strengths

Installed Base ConsumablesFormat Lock InRegulated Standards PipeDistribution ControlProcurement InertiaCapacity Moat

Segment mix

Marsh & McLennan Companies, Inc. segments

Full profile >

Risk and Insurance Services

Oligopoly

62.8%

Consulting

Competitive

37.2%

Thermo Fisher Scientific Inc. segments

Full profile >

Life Sciences Solutions

Oligopoly

19%

Analytical Instruments

Oligopoly

17%

Specialty Diagnostics

Oligopoly

10.4%

Laboratory Products and Biopharma Services

Competitive

53.6%

Want the full wide moat stocks list?

Browse the full ranking of wide moat stocks, updated with moat scores and segment context.

View the moat stocks list

Curation & Accuracy

This directory blends AI‑assisted discovery with human curation. Entries are reviewed, edited, and organized with the goal of expanding coverage and sharpening quality over time. Your feedback helps steer improvements (because no single human can capture everything all at once).

Details change. Pricing, features, and availability may be incomplete or out of date. Treat listings as a starting point and verify on the provider’s site before making decisions. If you spot an error or a gap, send a quick note and I’ll adjust.