VOL. XCIV, NO. 247

★ WIDE MOAT STOCKS COMPARISON ★

NO ADVICE

Sunday, January 11, 2026

Stock Comparison

Arthur J. Gallagher & Co. vs Thermo Fisher Scientific Inc.

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

Arthur J. Gallagher & Co.

AJG · New York Stock Exchange

Market cap (USD)$67.9B
Gross margin (TTM)
Operating margin (TTM)
Net margin (TTM)
SectorFinancials
IndustryInsurance - Brokers
CountryUS
Data as of2026-01-09
Moat score
69/ 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 Arthur J. Gallagher & Co.'s moat claims, evidence, and risks.

View AJG analysis

Thermo Fisher Scientific Inc.

TMO · New York Stock Exchange

Market cap (USD)$234.6B
Gross margin (TTM)39.8%
Operating margin (TTM)18.2%
Net margin (TTM)15%
SectorHealthcare
IndustryMedical - Diagnostics & Research
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: Arthur J. Gallagher & Co. leads (69 / 100 vs 64 / 100 for Thermo Fisher Scientific Inc.).
  • Segment focus: Arthur J. Gallagher & Co. has 2 segments (86% in Brokerage); 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: Arthur J. Gallagher & Co. has 4 moat types across 2 domains; Thermo Fisher Scientific Inc. has 8 across 3.

Primary market context

Arthur J. Gallagher & Co.

Brokerage

Market

Insurance and reinsurance brokerage and consulting

Geography

Global

Customer

Commercial, industrial, public sector, nonprofit and other organizations; underwriting enterprises for reinsurance placements

Role

Intermediary / broker / advisor

Revenue share

86%

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

Arthur J. Gallagher & Co.
Thermo Fisher Scientific Inc.
Ticker / Exchange
AJG - New York Stock Exchange
TMO - New York Stock Exchange
Market cap (USD)
$67.9B
$234.6B
Gross margin (TTM)
n/a
39.8%
Operating margin (TTM)
n/a
18.2%
Net margin (TTM)
n/a
15%
Sector
Financials
Healthcare
Industry
Insurance - Brokers
Medical - Diagnostics & Research
HQ country
US
US
Primary segment
Brokerage
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
69 / 100
64 / 100
Moat domains
Supply, Demand
Demand, Supply, Legal
Last update
2026-01-09
2025-12-22

Moat coverage

Shared moat types

Service Field NetworkBrand Trust

Arthur J. Gallagher & Co. strengths

Data Workflow LockinOperational Excellence

Thermo Fisher Scientific Inc. strengths

Installed Base ConsumablesFormat Lock InRegulated Standards PipeDistribution ControlProcurement InertiaCapacity Moat

Segment mix

Arthur J. Gallagher & Co. segments

Full profile >

Brokerage

Oligopoly

86%

Risk Management

Competitive

14%

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?

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Proven models entering the expansion stage with unit economics that work.

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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.