Marsh & McLennan Rises 0.79% as $0.46 Billion Volume Ranks 238th Amid Regulatory Shifts and Reinsurance Demand

Marsh & McLennan (MMC) closed 0.79% higher on October 3, 2025, with a trading volume of $0.46 billion, ranking 238th among listed stocks. The move followed mixed signals from market participants assessing the firm’s risk management services amid evolving regulatory frameworks in key markets. Analysts noted renewed institutional interest in the sector as firms recalibrate portfolios to hedge against macroeconomic uncertainties.

Recent commentary highlighted Marsh’s strategic positioning in the reinsurance brokerage segment, with clients reportedly increasing consultations on catastrophe modeling tools. A Bloomberg-verified report indicated that several major insurers have begun reallocating capital toward specialized risk analytics, a core competency for Marsh. However, some observers cautioned that margin pressures from lower-than-expected renewal rates in North America could temper near-term growth expectations.

To run this back-test properly I need to pin down a few practical details: Universe • Should we consider all common stocks listed on NYSE + NASDAQ (i.e., U.S. equities only), or a different universe? Selection timing & trade execution • Rank by the previous day’s dollar trading volume, or by share volume? • Enter the positions at the next day’s open and exit at that same day’s close (≈ one-day intraday hold), or enter at today’s close and exit at tomorrow’s close? Portfolio construction • Equal-weight across the 500 names each day? • Any transaction-cost assumption (e.g., 5 bps per leg) or ignore costs? Once I have these points I can generate the daily trade signals and run the back-test from 2022-01-03 to the latest available date.