Shares of Marsh & McLennan (MMC) tumbled 5.76% in pre-market trading on Thursday following the release of its first-quarter earnings report, which revealed mixed results that fell short of analyst expectations in key areas. The global professional services firm, which provides strategy, risk, and people solutions, reported figures that disappointed investors despite some positive aspects.

Marsh & McLennan posted Q1 revenue of $7.061 billion, missing the IBES estimate of $7.083 billion. More significantly, the company's adjusted operating income came in at $1.8 billion, substantially below the IBES estimate of $2.191 billion. This considerable shortfall in operating income likely contributed heavily to the negative market reaction. On a brighter note, the company's adjusted earnings per share (EPS) of $3.06 managed to edge out the IBES estimate of $3.02.

The company's largest segment, risk and insurance services, saw an 11% increase in revenue to $4.76 billion. However, this figure still fell short of analyst expectations, adding to investor concerns. The consulting business provided a silver lining, with revenue rising 5% and surpassing forecasts. Despite these mixed results, the overall market sentiment appears to be focusing on the missed targets, particularly in revenue and operating income, leading to the significant pre-market decline in Marsh & McLennan's stock price.