VOL. XCIV, NO. 247

★ WIDE MOAT STOCKS COMPARISON ★

NO ADVICE

Friday, January 2, 2026

Stock Comparison

AstraZeneca PLC vs Merck & Co., Inc.

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

AstraZeneca PLC

AZN · London Stock Exchange

Market cap (USD)
Gross margin (TTM)
Operating margin (TTM)
Net margin (TTM)
SectorHealthcare
Industry
CountryGB
Data as of2026-01-02
Moat score
71/ 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 AstraZeneca PLC's moat claims, evidence, and risks.

View AZN analysis

Merck & Co., Inc.

MRK · New York Stock Exchange

Market cap (USD)$266.4B
Gross margin (TTM)78.3%
Operating margin (TTM)36.4%
Net margin (TTM)29.6%
SectorHealthcare
IndustryDrug Manufacturers - General
CountryUS
Data as of2025-12-22
Moat score
71/ 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 Merck & Co., Inc.'s moat claims, evidence, and risks.

View MRK analysis

Comparison highlights

  • Moat score: both at 71 / 100.
  • Segment focus: AstraZeneca PLC has 6 segments (41% in Oncology); Merck & Co., Inc. has 2 segments (89.5% in Pharmaceutical).
  • Primary market structure: Oligopoly vs Competitive. Pricing power: Strong vs Moderate.
  • Moat breadth: AstraZeneca PLC has 4 moat types across 3 domains; Merck & Co., Inc. has 5 across 3.

Primary market context

AstraZeneca PLC

Oncology

Market

Innovator oncology therapeutics (branded prescription medicines)

Geography

Global

Customer

Hospitals, oncology clinics, payers

Role

Innovator biopharmaceutical company

Revenue share

41%

Merck & Co., Inc.

Pharmaceutical

Market

Branded prescription pharmaceuticals & human vaccines

Geography

Global

Customer

Wholesalers/retailers, managed care and government payers, hospitals/clinics

Role

R&D-intensive innovator, manufacturer, and marketer

Revenue share

89.5%

Side-by-side metrics

AstraZeneca PLC
Merck & Co., Inc.
Ticker / Exchange
AZN - London Stock Exchange
MRK - New York Stock Exchange
Market cap (USD)
n/a
$266.4B
Gross margin (TTM)
n/a
78.3%
Operating margin (TTM)
n/a
36.4%
Net margin (TTM)
n/a
29.6%
Sector
Healthcare
Healthcare
Industry
n/a
Drug Manufacturers - General
HQ country
GB
US
Primary segment
Oncology
Pharmaceutical
Market structure
Oligopoly
Competitive
Market share
n/a
n/a
HHI estimate
n/a
n/a
Pricing power
Strong
Moderate
Moat score
71 / 100
71 / 100
Moat domains
Legal, Supply, Demand
Legal, Supply, Demand
Last update
2026-01-02
2025-12-22

Moat coverage

Shared moat types

Regulated Standards PipeIP Choke PointCapex Knowhow Scale

AstraZeneca PLC strengths

Brand Trust

Merck & Co., Inc. strengths

Scope EconomiesData Workflow Lockin

Segment mix

AstraZeneca PLC segments

Full profile >

Oncology

Oligopoly

41%

Cardiovascular, Renal and Metabolism (CVRM)

Competitive

23%

Respiratory & Immunology (R&I)

Oligopoly

15%

Vaccines & Immune Therapies (V&I)

Oligopoly

3%

Rare Disease

Oligopoly

16%

Other Medicines

Competitive

2%

Merck & Co., Inc. segments

Full profile >

Pharmaceutical

Competitive

89.5%

Animal Health

Oligopoly

9.2%

Want the full wide moat stocks list?

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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.