Mayer Brown Posts Record £268M London Revenue as Latham Guides Belgian Investor on €500M Cross-Border Traffic Deal
Mayer Brown has reported record revenue of $268 million from its London office, marking a significant milestone for the US firm's international platform. Separately, Latham & Watkins is advising a Belgian investor on a €500 million deal for a traffic management business, underscoring the continued cross-border M&A appetite among European institutional buyers despite macro uncertainty. Together, the two data points illustrate the dual engines driving international law firm performance in London: organic revenue growth from deepening local practices, and high-value cross-border transaction mandates from continental European clients deploying capital into infrastructure-adjacent sectors. The Latham mandate is notable for its size — €500 million places it firmly in the upper tier of European mid-market deals — and for the Belgian buyer profile, reflecting sustained Benelux outbound M&A activity into specialist business services. For Mayer Brown, the London record adds to a broader narrative of US firms consolidating top-tier positions in the City, competing directly with the Magic Circle on transactional and finance work.
Why this matters
Mayer Brown's $268 million London revenue record signals that US firms with deep City roots are moving beyond challenger status and competing at scale on the international stage. The Latham-advised €500 million Belgian traffic deal demonstrates that European strategic buyers remain acquisitive in regulated, data-driven infrastructure sectors notwithstanding rate and geopolitical headwinds. Combined, the two stories reflect a bifurcated but buoyant international deal environment: large-cap US firms capturing London market share while continental European capital continues to seek cross-border deployment. For trainees and associates, both mandates highlight the premium placed on lawyers who can navigate multi-jurisdictional structures and advise clients across common law and civil law systems simultaneously.
On the Ground
Expect due diligence checklists on cross-border traffic and mobility assets to require specialist regulatory sign-off in each operating jurisdiction. On the firm performance side, watch for Magic Circle and Silver Circle responses to US firm London revenue disclosures as league-table positioning intensifies ahead of partner promotion season.
Interview prep
Soundbite
US firms are no longer challengers in London — they are setting the revenue benchmark.
Question you might get
“How does a US firm like Mayer Brown compete with Magic Circle firms for top London mandates, and what does record London revenue actually tell us about firm strategy?”
Full answer
Mayer Brown's record $268 million London revenue reflects a structural shift: US firms with longstanding City offices have built practices broad enough to compete with UK-headquartered elite firms on both transactional volume and premium work quality. At the same time, the Latham-advised €500 million Belgian traffic deal shows that cross-border M&A mandates — particularly in infrastructure-adjacent sectors — remain a primary driver of international revenue. Belgian and broader Benelux buyers have remained active acquirers through the current rate cycle, favouring businesses with recurring, regulated revenue streams. For a junior lawyer, the practical implication is that international deal teams demand fluency in multi-jurisdictional structuring, foreign regulatory clearance processes, and the ability to coordinate across offices in real time.
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