Simpson Thacher & Bartlett and CMS headed the European mergers and acquisitions legal adviser rankings in the first quarter of 2026, taking the top spots by deal value and deal count respectively, based on GlobalData’s latest league table.
Figures from GlobalData’s Financial Deals Database show Simpson Thacher & Bartlett was involved in transactions worth a combined $48.2bn, placing it first by value.
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Kirkland & Ellis was next with $45.5bn, followed by A&O Shearman on $37.2bn, Herbert Smith Freehills Kramer on $21.6bn and White & Case on $18bn.
In the ranking by number of deals, CMS came first with 37 transactions.
White & Case took second place with 32 deals, ahead of DLA Piper with 30. A&O Shearman recorded 27 deals, while Latham & Watkins advised on 22.
Aurojyoti Bose, lead analyst at GlobalData, commented: “CMS was the top adviser by volume in Q1 2025 and retained its leadership in position by this metric in Q1 2026 as well, despite registering a year-on-year (YoY) drop in the number of deals advised.
“Meanwhile, Simpson Thacher & Bartlett’s ranking by value jumped from the 21st position in Q1 2025 to the top position in 2026. The involvement in $33.4bn deal for the acquisition of AES by consortium of acquirers played a pivotal role in Simpson Thacher & Bartlett securing the top spot by value in Q1 2026.”
GlobalData’s league tables are based on the real-time tracking of thousands of company websites, advisory firm websites and other reliable sources available on the secondary domain. A dedicated team of analysts monitors all these sources to gather in-depth details for each deal, including adviser names.
To ensure further robustness to the data, the company also seeks submissions of deals from leading advisers.
