Simpson Thacher & Bartlett and CMS were the top mergers and acquisitions (M&A) legal advisers in Europe during the first quarter (Q1) of 2026 by value and volume, respectively according to the latest legal advisers league table by GlobalData, a leading intelligence and productivity platform.

An analysis of GlobalData’s Financial Deals Database reveals that Simpson Thacher & Bartlett achieved the leading position in terms of value by advising on $48.2 billion worth of deals. Meanwhile, CMS led in terms of volume by advising on a total of 37 deals.

Aurojyoti Bose, Lead Analyst at GlobalData, comments: “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 $33.4 billion 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.”

Kirkland & Ellis occupied the second position in terms of value, by advising on $45.5 billion worth of deals, followed by A&O Shearman with $37.2 billion, Herbert Smith Freehills Kramer with $21.6 billion and White & Case with $18 billion.

Meanwhile, White & Case occupied the second position in terms of volume with 32 deals, followed by DLA Piper with 30 deals, A&O Shearman with 27 deals and Latham & Watkins with 22 deals.