Oliver Wyman

Carbon per million dollars of revenue. The legacy industry-standard reference (CDP, MSCI). Useful for cross-sector context, but distorted by margin — high-margin firms appear artificially efficient. Read alongside the operational and asset intensities for the full picture.

OpEx (operating expenditure) is the running cost of the business — staff, services, energy, materials. This shows how carbon-intensive operations are per million dollars of spend. Removes the margin distortion that revenue-based ratios introduce.

EVIC (Enterprise Value Including Cash) is the firm's total capital footprint — equity + debt + cash + minority interest. The EU's standard intensity measure (SFDR PAI 3) — answers: how much carbon does each million of capital deployed in this business produce?

PP&E (Property, Plant & Equipment) plus leased real-estate assets is the firm's physical infrastructure on the balance sheet. This shows the carbon intensity of that physical footprint — uses Scope 1+2+3 for consistency with the other headline intensities. Surfaces stranded-asset risk for asset-heavy firms.

Carbon per FTE (full-time-equivalent employee) — the diagnostic measure for people-leveraged businesses where headcount, not capital, drives delivery. Captures the office, energy and travel footprint per person.

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• · Puro.earth Registry
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Marsh has rapidly scaled renewable electricity from 13% in 2019 to 76% in 2024 and 84% in 2025 across its global office portfolio. Renewable electricity is one of the firm's primary control levers for Scope 2 reductions (market-based Scope 2 fell from 83,293 tCO2e in 2019 to 7,964 tCO2e in 2025, a ~90% reduction).

Marsh's offset portfolio composition is 38% reduction, 37% avoidance, and 25% removal credits. The firm invests in emissions-avoidance and carbon-removal pathways outside its value chain alongside its science-based reduction trajectory. Project selection criteria include quality, location, additionality, and UN SDG alignment. Disclosed via California AB-1305.

• Business travel reduction

  Business travel (Scope 3 Cat 6) is one of Marsh's largest Scope 3 categories at 108,238 tCO2e in 2025, down from 113,708 in 2024. Included in the firm's CarbonNeutral certification scope, and addressed via internal policies that empower colleagues to make more sustainable travel choices.

• Office energy efficiency — Wireless Centric Office and Smart Offices

  Throughout 2025 Marsh continued upgrading offices to its Wireless Centric Office format — wireless access points + energy-efficient switches use ~40% less cabling and 90% less power. Once rolled out across the portfolio by end of 2026, expected to save ~12 million kWh annually in electricity. 172 Smart Offices opened in 51 countries as of Dec 31, 2025. Strategic space planning has driven a 24% reduction in office space per FTE since 2019 (172 → 130 sq ft).

• Fleet rationalization and electrification

  Marsh identifies fleet rationalization and electrification among its levers under control. Scope 1 emissions (largely company car fleet and space heating) were 21,108 tCO2e in 2025, down from 25,496 tCO2e in 2019.

• Fleet electrification

  Introducing electric vehicles to the company fleet; as of December 31, 2024, the fleet is 30% hybrid and electric vehicles. Fleet rationalization and electrification is a stated lever in the SBTi transition strategy.

• Office energy efficiency and smart offices

  167 smart offices opened in 50 countries with energy-efficient lighting, HVAC and energy-management systems. Square footage per FTE rationalized by 39% since 2019. Implemented timed shut-offs in video conferencing rooms, energy-saving settings on computer equipment, and occupancy sensors.

• Office footprint optimisation & Smart Office program

  Reduced square footage per full-time colleague by 31% since 2019. Opened 115 smart offices since 2016 incorporating energy-saving lighting and HVAC, water-conserving fixtures, and waste-reduction practices. Continued server virtualization and migration of data centers from on-premises to cloud hosting; implemented smart energy management settings in approximately 2,500 Zoom rooms worldwide.

• Waste reduction, e-waste recycling and furniture reuse

  70% of offices have implemented centralized waste collection; 4.6 million pounds of e-waste recycled since 2016. Eliminated single-use plastics in pantries; piloting reusable to-go containers at London HQ. At NY HQ, 95% of construction waste diverted from landfill on a recent project (272,000 lb CO2 avoided); in Singapore, 100% of furniture and monitors sourced via internal reuse during a recent renovation.

• Business travel reduction via internal carbon pricing

  Business travel is one of the largest emissions sources (103,590 tCO2e in 2023). Oliver Wyman Group implemented an internal price on carbon for business travel to incentivize purposeful and value-added travel. Marsh McLennan is monitoring this program's design and outcomes to understand the role it may play in reducing business travel emissions across the wider enterprise.

• Cloud infrastructure / IT decarbonisation

  Marsh McLennan Global Technology Infrastructure (MGTI) accelerated migration to Microsoft 365 SaaS tools (100% colleagues migrated by mid-2022). Retired 16 servers in 2021 with 275 more planned for 2022 as data moves to public cloud. Global IT Asset Disposal (ITAD) program retired 10,500+ older laptops in 2021 replaced with energy-efficient models; ~3.6M lbs e-waste recycled over 8 years.

• Business travel reduction via Green Traveler program

  Business travel (Scope 3 air travel) is the dominant addressable scope-3 category for MMC. The Green Traveler program includes a 3-minute educational video, Purposeful Travel Guide questionnaire and Tips for Greener Travel. Air travel emissions fell from 79,556 tCO2e in 2019 to 7,398 tCO2e in 2021. The firm commits to use travel alternatives even as travel rebounds.

• Office energy efficiency via Smart Office initiative

  Since 2016, MMC has opened 51 Smart Offices in 22 countries housing ~14,000 colleagues, with creative space design, energy-efficient lighting and HVAC, and construction practices focused on waste reduction. Nine more offices under construction including NYC and London. Scope 2 reduction from 2020 to 2021 reflects more efficient energy grids and reduced real estate footprint.

• Supplier engagement on purchased goods and services

  Emissions from purchased goods and services represented over 50% of Marsh's emissions in 2025 (342,849 tCO2e). The firm focuses engagement on strategic and priority suppliers based on size of spend, emissions, and maturity. Major cloud service providers have set 100% renewable electricity targets. 100% of electronics purchased in 2025 were EPEAT certified, avoiding over 11,000 metric tons of CO2e.

• Responsible AI use to limit AI energy footprint

  Marsh's proprietary LenAI tool handles 34.3 million queries annually. The firm intentionally avoids large-scale model training unless there is a strong business case, partners with AI and cloud providers that have set climate targets, and provides colleagues with guidance on efficient prompting and selecting the most efficient model for each task.

• Business travel reduction

  Scope 3 Category 6 business travel was 109,904 tCO2e in 2024. Business travel is one of the named SBTi near-term target categories (purchased goods, capital goods, business travel; 55% reduction per million USD operating profit by 2030).

• Supplier engagement on purchased goods & services

  Cat 1 (purchased goods & services) represented over 50% of 2024 emissions. Approach: improve data quality by moving from spend-based to activity-based accounting; engage suppliers via supplier-management platform; environmentally preferred purchasing guidance (energy efficiency, recycled content, certifications).

• Supplier engagement on Scope 3 purchased goods & services

  Purchased goods and services (Cat 1 = 265,624 tCO2e in 2022) is the largest Scope 3 category. Held meetings with key suppliers across technology, IT, office furniture and office supplies categories to learn about sustainability activities, share best practices, and identify collaboration opportunities. Plans to calculate Scope 3 emissions from purchased goods and services more rigorously going forward.

• Single-use plastics elimination in office pantries

  In January 2021 committed to eliminating single-use plastics and reducing single-use waste in all office pantries globally by end of 2022. As of year-end 2021, 50% of offices (housing 50% of colleagues) had eliminated single-use plastics.