Marsh McLennan gears up for massive AWS migration

Dive Brief:

• Marsh McLennan plans to migrate most of its on-premises infrastructure to AWS as part of a multiyear deal with the hyperscaler, the two companies said Wednesday. The 150-year-old professional services firm will leverage cloud to enhance security, drive efficiencies and bolster AI capabilities across its four divisions — Marsh, Guy Carpenter, Mercer and Oliver Wyman — according to the announcement.
• “We’re setting up our IT infrastructure in a way that’s going to give us the maximum agility in the long run, manage our costs in the near term, but also just give us the flexibility to evolve and adapt as our business needs evolve,” Paul Beswick, Marsh McLennan’s chief information and operations officer, said in an AWS video presentation.
• The company will take a phased approach to shuttering several strategic data centers, leaving the largest one for last, according to Beswick. “The program has been built to make sure that we’re learning as we go and, in particular, that we are increasing the level of automation that we have as we go, so that when we get to the big beast at the end, we have a slicker, more finely tuned process,” he said.

Dive Brief:

AWS pumped tens of billions of dollars into its sprawling cloud empire to expand capacity over the last year, largely to increase its AI processing power. A surge in enterprise workload migrations also contributed to an industrywide building boom, which drove a 51% year-over-year spike in global data center investments last year..

“We see an increased resurgence, and understanding for enterprises that they’re dropping the low-hanging fruit if they don’t move their infrastructure to the cloud,” said Amazon VP of Investor Relations Dave Fildes, during the company’s Q1 2025 earnings call. “That is typically a multiyear process … some companies do it fast, some companies do it slower, but they do it cautiously … because they can’t afford for their application not to work if they’re making that transition.”

Marsh McLennan was mindful of potential disruptions when plotting the massive migration effort, according to Beswick.

“The critical point was finding the moment where we could adopt an approach which was primarily lift-and-shift, make the economics work and then push back the modernization and the optimization phase until afterwards and tackle that at our leisure,” Beswick said.

The company will continue to run some workloads on premises to comply with existing data management agreements, according to the announcement. It will also focus on cultivating cloud skills through AWS training assets.

In addition to tapping AWS for migration and training services, Marsh McLennan aims to bolster an already robust AI deployment strategy through the hyperscaler partnership.

Marsh McLennan was quick to see the value in large language model capabilities. In November 2023, the company armed its now more than 90,000-person workforce with an internally hosted generative AI tool, called LenAI, that was built using OpenAI and Microsoft services.

The AI assistant handles over 700,000 queries weekly and saves an estimated one million productivity hours per year, according to the company.

“One of the things that I feel most glad about recently is taking a bet on AI before I was asked about it,” Beswick said. “Being slightly ahead of everyone is a nicer place to be than being slightly behind.”

The company’s internal processes will have to evolve again as more applications move to the cloud, Beswick acknowledged, but that’s part of the plan. “You don’t get to be 150 years old without dealing with a fair amount of change along the way,” he said.