Which Biglaw firms racked up the biggest mergers and acquisitions deals in 2017? Digging into which firms’ M&A departments had the best 2017 is the motivation behind Big Law Business’s annual ranking of law firms by M&A deal volume. In the latest edition of the ranking, there was a good deal of reshuffling at the top of the list, but by far the biggest move was made by Cleary Gottlieb, which doubled its market share in 2017:
But one of the most striking moves came from Cleary Gottlieb Steen & Hamilton, which doubled its market share to claim spot 3 with a slew of big-dollar deals. The firm advised principals on just 85 deals with a total value of $259 billion.
“2017, from our perspective, was a year where a lot of companies did arguably their most important transactions in a long time, and that plays into our strength,” partner Ethan Klingsberg told Big Law Business.
These rankings only include the work done for the corporations buying a target or selling to a buyer — no credit is given for a firm that just advised a bank or investment firm in those transactions. Even Bloomberg — the creator of the ranking — recognizes the limitations of the methodology:

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Of course, the year-to-year rankings of law firms provide a snapshot of their M&A performance and should be taken with a grain of salt. For example, some firms may have been quite busy in 2017 working on large deals that won’t be announced until this year, or they may have spent significant resources helping clients ward off a takeover. They could be billing significant hours on these matters, but it won’t get them on the league tables.
Still, the data provides a clear metric to rank the firms by — and who doesn’t like a good old fashioned ranking? So, without further ado, the Top 10 Law Firms by M&A Deal Volume in 2017:
Law Firms By M&A Deal Volume (2017) | |||
Rank | Firm | Market Share (%) | Volume USD (Mln) |
1 | Skadden | 17.5 | $429,983 |
2 | Simpson Thacher | 10.7 | $263,012 |
3 | Cleary Gottlieb | 10.5 | $259,385 |
4 | Allen & Overy | 9.4 | $232,019 |
5 | Kirkland & Ellis | 9.0 | $220,729 |
6 | Davis Polk | 8.6 | $211,600 |
7 | Freshfields | 7.9 | $195,227 |
8 | Wachtell | 7.8 | $193,241 |
9 | Blake Cassels | 7.4 | $181,859 |
10 | Sullivan & Cromwell | 7.4 | $181,098 |
The good news for law firms is that 2018 is also shaping up to be a banner year:

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Stephen Arcano, who leads Skadden’s New York M&A group, also said he expects M&A activity to remain high in 2018. “The strategic drivers for M&A remain in place,” he said.
For the rest of the Top 20 and additional details about the firms, check out the full ranking at Big Law Business.
Kathryn Rubino is an editor at Above the Law. AtL tipsters are the best, so please connect with her. Feel free to email her with any tips, questions, or comments and follow her on Twitter (@Kathryn1).