Comparison

Arthur J. Gallagher & Co. (AJG) vs Aon plc (AON)

The same filed metrics for both companies, side by side.

What each names as a risk in its own annual report, how each is priced against its own history, and the tracked managers whose latest 13F reports a position in both.

Financials

AJG

Arthur J. Gallagher & Co.

Insurance Brokers

Revenue, FY25: $13.94B
Net income: $1.49B
Operating cash flow: $1.93B
Free cash flow: -
Net margin: 10.72%
Operating margin: -
Gross margin: -

AON

Aon plc

Insurance Brokers

Revenue, FY25: $17.18B
Net income: $3.75B
Operating cash flow: $3.48B
Free cash flow: $3.22B
Net margin: 21.83%
Operating margin: 25.28%
Gross margin: -

Head-to-head

Filed growth, quality and valuation, read against each company’s own history rather than against the other side.

Metric	AJG	AON
Revenue growth, latest filed year	+20.66%	+9.45%
Piotroski F-score	5 of 8	6 of 8
P/E against its own history	about normal	35.34% below

What each says it is exposed to

From Item 1A of each company’s most recent 10-K.

AJG

Cybersecurity
Data privacy
Litigation
Tax
Export controls
Inflation

And 16 more.

AON

Tax
Litigation
AI and its regulation
Cybersecurity
Data privacy
Currency moves

And 14 more.

Tracked managers holding both

Dodge & Cox Dodge & Cox 1.13% · 1.49%
Joel Greenblatt Gotham Asset Management 0.12% · 0.04%

Updated Sep 17, 2026 · the newer of the two companies' filings