VOL. XCIV, NO. 247

★ WIDE MOAT STOCKS COMPARISON ★

NO ADVICE

Wednesday, December 31, 2025

Stock Comparison

Aon plc vs Gilead Sciences, Inc.

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

Aon plc

AON · New York Stock Exchange

Market cap (USD)$76.6B
SectorFinancials
CountryIE
Data as of2025-12-31
Moat score
70/ 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 Aon plc's moat claims, evidence, and risks.

View AON analysis

Gilead Sciences, Inc.

GILD · NASDAQ Global Select Market

Market cap (USD)$155.6B
SectorHealthcare
CountryUS
Data as of2025-12-30
Moat score
74/ 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 Gilead Sciences, Inc.'s moat claims, evidence, and risks.

View GILD analysis

Comparison highlights

  • Moat score gap: Gilead Sciences, Inc. leads (74 / 100 vs 70 / 100 for Aon plc).
  • Segment focus: Aon plc has 2 segments (67% in Risk Capital); Gilead Sciences, Inc. has 5 segments (68.5% in HIV).
  • Moat breadth: Aon plc has 6 moat types across 3 domains; Gilead Sciences, Inc. has 8 across 3.

Primary market context

Aon plc

Risk Capital

Market

Large-account commercial insurance & reinsurance brokerage and risk advisory

Geography

Global

Customer

Enterprises, insurers, reinsurers

Role

Intermediary/advisor

Revenue share

67%

Gilead Sciences, Inc.

HIV

Market

HIV treatment and prevention medicines (antiretroviral therapy and PrEP)

Geography

Global (U.S. and Europe are major markets)

Customer

Patients/prescribers; reimbursed by public and private payers; distributed via wholesalers and specialty pharmacies

Role

Drug developer and marketing authorization holder

Revenue share

68.5%

Side-by-side metrics

Aon plc
Gilead Sciences, Inc.
Ticker / Exchange
AON - New York Stock Exchange
GILD - NASDAQ Global Select Market
Market cap (USD)
$76.6B
$155.6B
Sector
Financials
Healthcare
HQ country
IE
US
Primary segment
Risk Capital
HIV
Market structure
Oligopoly
Oligopoly
Market share
n/a
50%-60% (reported)
HHI estimate
n/a
n/a
Pricing power
Moderate
Moderate
Moat score
70 / 100
74 / 100
Moat domains
Demand, Supply, Legal
Demand, Legal, Supply
Last update
2025-12-31
2025-12-30

Moat coverage

Shared moat types

Switching Costs GeneralService Field NetworkBrand TrustCompliance Advantage

Aon plc strengths

Data Workflow LockinScale Economies Unit Cost

Gilead Sciences, Inc. strengths

Habit DefaultIP Choke PointCapex Knowhow ScaleRegulated Standards Pipe

Segment mix

Aon plc segments

Full profile >

Risk Capital

Oligopoly

67%

Human Capital

Oligopoly

33.2%

Gilead Sciences, Inc. segments

Full profile >

HIV

Oligopoly

68.5%

Oncology (Cell Therapy + Trodelvy)

Oligopoly

11.5%

Liver Disease

Oligopoly

10.6%

Veklury (Remdesivir)

Competitive

6.3%

Other Products

Competitive

3.1%

Want the full wide moat stocks list?

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

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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.