--- title: "Insurance Broker 13Fs: Marsh, Aon, Gallagher Through Smart Money" type: learn slug: insurance-broker-13f-mmc-ajg-decoder canonical_url: https://13finsight.com/learn/insurance-broker-13f-mmc-ajg-decoder published_at: 2026-05-16T14:35:16.149Z updated_at: 2026-05-16T14:35:21.885Z author: Sarah Mitchell author_title: Education Editor author_url: https://13finsight.com/authors/sarah-mitchell word_count: 583 locale: en source: 13F Insight --- # Insurance Broker 13Fs: Marsh, Aon, Gallagher Through Smart Money > Marsh McLennan, Aon, Arthur J. Gallagher, plus Brown & Brown and Willis Towers Watson anchor US insurance broker 13F positioning. Multi-year property-casualty pricing cycle, employee benefits consulting, plus emerging emerging M&A roll-up drive distinctive institutional patterns. US insurance broker equities form a distinctive financial services corner of institutional 13F positioning. Marsh McLennan (MMC), Aon (AON), Arthur J. Gallagher (AJG), Brown & Brown (BRO), plus Willis Towers Watson (WTW) anchor the cohort. Multi-year emerging property-casualty pricing cycle (hard market), employee benefits consulting growth, plus emerging emerging insurance broker M&A roll-up drive distinctive institutional positioning. Reading insurance broker 13F positioning requires understanding the commission framework plus the multi-year P&C cycle dynamics.The insurance broker business modelInsurance brokers operate four primary economic engines:Commission plus fee revenue. Insurance brokers earn commission from insurance carriers (typically 10-15% of premium) plus emerging fee revenue from clients. Multi-year emerging organic revenue growth tracks underlying premium plus emerging emerging carrier commission rates. Multi-year emerging fee revenue (employee benefits consulting, risk management consulting) drives diversification.Property-casualty pricing cycle. Multi-year emerging hard P&C market (2020-2024) drove emerging premium increases (commercial P&C rates +5 to +15% range) plus emerging emerging broker commission revenue tailwind. Multi-year emerging emerging P&C cycle softening (late 2024 onward) drives multi-year emerging organic growth deceleration. Multi-year emerging emerging hard market segments (cyber, professional liability, property catastrophe) drive selective tailwinds.Employee benefits consulting. Multi-year emerging employee benefits consulting growth (health insurance, retirement, voluntary benefits) drives multi-year recurring revenue. Multi-year emerging health insurance premium inflation (8-12% annual employer healthcare cost growth) drives consulting demand. Multi-year emerging emerging actuarial services plus emerging emerging benefits administration drives diversification.M&A roll-up. Multi-year emerging insurance broker M&A roll-up drives organic plus emerging emerging acquisition revenue growth. Multi-year emerging Marsh McLennan, Aon, Arthur J. Gallagher, plus emerging emerging Brown & Brown acquire 30-100+ smaller brokers annually. Multi-year emerging emerging private equity competition (Acrisure, Hub International, AssuredPartners) reshape competitive landscape.Major US insurance broker namesMarsh McLennan (MMC)Largest US insurance broker plus consulting (Marsh insurance broking, Guy Carpenter reinsurance, Mercer benefits, Oliver Wyman strategy). Multi-decade compounding plus emerging emerging McGriff Insurance Services acquisition (closed 2024 from TIH) plus emerging emerging operational scaling.Aon (AON)Second-largest US insurance broker plus consulting plus emerging emerging NFP Corp acquisition (closed April 2024) plus emerging emerging operational integration. Multi-year emerging Willis Towers Watson failed merger (2021) plus emerging emerging operational scaling.Arthur J. Gallagher (AJG)Diversified insurance broker plus consulting plus emerging emerging M&A roll-up (acquired 30+ brokers annually) plus emerging emerging Buck Consulting acquisition (closed 2023). Multi-year emerging operational scaling plus emerging emerging dividend discipline.Brown & Brown (BRO)Diversified insurance broker plus emerging emerging Retail plus emerging emerging Wholesale plus emerging emerging Services plus emerging emerging M&A roll-up. Multi-year emerging operational scaling plus emerging emerging dividend discipline plus emerging emerging founder-led culture.Willis Towers Watson (WTW)Diversified insurance broker plus consulting (Willis Re reinsurance divested 2021 to AJG). Multi-year emerging operational restructuring plus emerging emerging operational scaling plus emerging emerging consulting positioning.How institutional managers position around insurance brokersThree patterns appear across smart-money 13Fs:Pattern 1: Quality-compounder concentrationMMC, AJG, BRO-concentrated growth manager positions reflect quality compounding plus emerging emerging M&A roll-up thesis.Pattern 2: M&A-integration positioningAON-concentrated active manager positions reflect NFP integration plus emerging emerging operational synergy thesis.Pattern 3: Turnaround positioningWTW-concentrated value-discipline manager positions reflect operational recovery plus emerging emerging margin expansion thesis.How to read insurance broker 13F positioningThree rules apply:Rule 1: Identify business mixP&C-emphasis vs benefits-consulting vs reinsurance have distinct dynamics.Rule 2: Watch P&C cycleMulti-year P&C pricing cycle drives organic growth.Rule 3: Cross-check M&A activityMulti-year M&A roll-up drives revenue growth.What insurance broker positioning signalsQuality-compounder conviction. Concentrated MMC, AJG, BRO positions signal quality compounding thesis.M&A-integration conviction. Concentrated AON positions signal NFP integration thesis.Turnaround conviction. Concentrated WTW positions signal operational recovery thesis.For real-time tracking of insurance broker 13F activity, see the institutional signals feed. ## FAQ ### What are the major US insurance brokers? Five major US insurance brokers: (1) Marsh McLennan (MMC) — largest US, Marsh plus Guy Carpenter plus Mercer plus Oliver Wyman; (2) Aon (AON) — second-largest plus NFP acquisition; (3) Arthur J. Gallagher (AJG) — diversified plus M&A roll-up; (4) Brown & Brown (BRO) — Retail plus Wholesale plus Services; (5) Willis Towers Watson (WTW) — broker plus consulting. Plus private equity-owned Acrisure, Hub, AssuredPartners. ### How does the property-casualty pricing cycle work? Multi-year hard P&C market (2020-2024) drove commercial P&C rate increases (+5 to +15% range) plus emerging broker commission revenue tailwind. Multi-year P&C cycle softening (late 2024 onward) drives organic growth deceleration. Hard market segments (cyber insurance +20-30%, professional liability, property catastrophe) drive selective tailwinds. Reading P&C rate trajectory drives broker positioning. ### How does insurance broker M&A roll-up work? Multi-year insurance broker M&A roll-up drives organic plus acquisition revenue growth. Major roll-ups: Marsh McLennan (McGriff acquired 2024), Aon (NFP acquired 2024), Arthur J. Gallagher (30+ brokers annually plus Buck Consulting), Brown & Brown (30-50 brokers annually). Multi-year private equity competition (Acrisure, Hub International, AssuredPartners) emerging emerging escalates target valuations. Reading acquisition cadence drives positioning. ### How does employee benefits consulting work? Employee benefits consulting includes health insurance brokerage, retirement plan consulting, voluntary benefits, actuarial services, plus emerging benefits administration. Multi-year health insurance premium inflation (8-12% annual employer healthcare cost growth) drives consulting demand. Multi-year emerging high-deductible health plan adoption plus emerging emerging employee voluntary benefits (life, disability, dental, vision) drive recurring revenue. ### What was the Aon-Willis Towers Watson failed merger? Aon announced March 2020 all-stock acquisition of Willis Towers Watson at $30B valuation. DOJ filed antitrust lawsuit June 2021 alleging the combined entity would harm competition in commercial risk brokerage plus reinsurance brokerage plus pension benefits consulting. Aon-WTW terminated July 2021 with Aon paying $1B breakup fee. Multi-year post-merger broker landscape (Willis Re divested to AJG) reshape competitive dynamics. ### What signals insurance broker cycle inflections? Four signals: (1) P&C rate trajectory plus emerging organic growth dynamics; (2) M&A activity plus emerging acquisition cadence; (3) employee benefits consulting growth plus emerging healthcare cost trajectory; (4) margin expansion plus emerging operational discipline. Concentrated 13F changes around these signals reveal manager cycle reading. --- Source: 13F Insight — https://13finsight.com/learn/insurance-broker-13f-mmc-ajg-decoder Author: Sarah Mitchell — https://13finsight.com/authors/sarah-mitchell Last updated: 2026-05-16T14:35:21.885Z