Arthur J. Gallagher vs Marsh & Mclennan Companies (AJG vs MMC)
Side by side from their SEC filings: revenue, margins, growth, returns and valuation, plus short interest, insider activity and institutional ownership.
Marsh & Mclennan Companies is the larger company by revenue ($27.0B vs $13.9B) and market value ($86.0B vs $65.0B). Arthur J. Gallagher has grown revenue faster over the last 4 fiscal years (+69.8% cumulative vs +36.1%). Marsh & Mclennan Companies trades at the lower trailing P/E (22.3x vs 41.0x).
About Arthur J. Gallagher
Arthur J. Gallagher & Co. provides insurance brokerage, reinsurance brokerage, consulting, and third-party property and casualty claims settlement and administration services globally. The company serves commercial, nonprofit, public sector entities, insurance companies, and individuals through its brokerage and risk management segments. Its services include placing insurance and reinsurance coverage, managing risk and employer-sponsored benefit programs, and administering claims for self-insured entities.
About Marsh & Mclennan Companies
Marsh & McLennan Companies, Inc. provides risk management, insurance and reinsurance brokerage, and consulting services worldwide. Its Risk and Insurance Services segment includes Marsh Risk, which offers insurance broking, risk advisory, and program management, and Guy Carpenter, which specializes in reinsurance broking and strategic advisory. The Consulting segment delivers health, wealth, career advice, and management consulting services through Mercer and Marsh Management Consulting to organizations globally.
Head to head (AJG FY2025 vs MMC FY2025)
| Metric | AJGFY2025 | MMCFY2025 |
|---|---|---|
| Revenue | $13.94B | $26.98B |
| Revenue growth (YoY) | 20.7% | 10.3% |
| Gross margin | — | — |
| Operating margin | — | 23.1% |
| Net margin | 10.7% | 15.4% |
| Net income | $1.49B | $4.16B |
| Diluted EPS | $5.74 | $8.43 |
| FCF margin | — | 18.5% |
| ROE | 6.4% | 27.2% |
| Debt / equity | 0.5× | 1.2× |
| Market cap | $65.03B | $86.02B |
| P/E (TTM) | 41.0× | 22.3× |
Fundamentals are from each company’s SEC filings (AJG FY2025, MMC FY2025). P/E and market cap are derived from recent market prices and update daily.
Five-year trend (as reported)
| Revenue | FY2021 | FY2022 | FY2023 | FY2024 | FY2025 |
|---|---|---|---|---|---|
| AJG | $8.21B | $8.55B | $10.07B | $11.55B | $13.94B |
| MMC | $19.82B | $20.72B | $22.74B | $24.46B | $26.98B |
Peer standing
Where each company ranks among the 88 insurance companies, on the same scale. Each figure is ranked only against peers that report it. Percentiles describe position in the distribution, not a rating.
| Metric | AJG | MMC |
|---|---|---|
| Net margin | 10.7%48th percentile of 82 | 15.4%69th percentile of 82 |
| Revenue growth (YoY) | +20.7%68th percentile of 88 | +10.3%54th percentile of 88 |
| ROE | 6.4%24th percentile of 73 | 27.2%83rd percentile of 73 |
| P/E (TTM) | 41.0×89th percentile of 71 | 22.3×80th percentile of 71 |
| Debt / equity | 0.52×77th percentile of 48 | 1.20×87th percentile of 48 |
| Short interest (days to cover) | 3.36d60th percentile of 86 | 2.08d28th percentile of 86 |
Short interest
| FINRA settlement data | AJG | MMC |
|---|---|---|
| Shares sold short | 6.8M | 5.0M |
| Change vs prior settlement | -0.8% | -5.2% |
| Days to cover | 3.36 | 2.08 |
| As of settlement | 2026-06-30 | 2025-12-31 |
Source: FINRA Consolidated Short Interest. FINRA is the owner and source of the FINRA-supplied data; republishing or redistributing it is not permitted. Not presented as a percentage of float. No FINRA endorsement of this product is implied.
Insider activity (last 90 days)
| Form 4 open-market activity | AJG | MMC |
|---|---|---|
| Buys | 0 | — |
| Sells | 1 ($618,000) | — |
Open-market purchases and sales reported on SEC Form 4 (grants, exercises and tax withholding excluded). For context, about 16% of covered companies saw any open-market insider buy in a 90-day window.
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Data sourced from SEC EDGAR (public domain). Figures are as-reported and may be unaudited or restated; verify against the source filings before relying on them. Comparisons are descriptive (higher or lower on a reported figure), not a rating or a recommendation. Informational only. Not investment advice.