While 2023 held the record for sheer volume of M&A deals, 2025 emerged as the highest year on record for total deal valuation (over the past five years). Three mergers in particular stood out:

Even before the end of Q1 2026, four major mergers had already been announced or completed. These are collectively expected to affect 8,200 lawyers. For context, the eight mega-mergers of 2025 affected approximately 10,000 lawyers across the full year.

The four deals to watch:

Running in parallel to the surge in M&A activity is a rapid increase in AI investment across the legal sector. According to data from the Thomson Reuters Institute, law firm spend on legal technology has nearly tripled in the past three years, driven largely by the rise of generative AI.

Are these two trends connected? AI investment may not be direct cause of increased merger activity, but there is a compelling case for why firms might pursue both strategies simultaneously:

1. Scale and economics

As agentic AI systems become more powerful and more expensive, smaller and mid-sized firms may find it increasingly difficult to compete. Last year, a Harvard Business School article highlighted that tools like Harvey and Leya could price out firms that lack the budget or scale to integrate them effectively. Mergers can enable firms to pool their innovation budgets and accelerate AI adoption.

2. Proprietary data advantage

Mergers also allow firms to consolidate their internal datasets across practice of law and business services. This means firms can reach the critical mass required to train and refine custom AI systems.

This intersection of M&A strategy and technology investment is a trend worth watching closely.

Looking across the deals of 2025 and early 2026, Pirical's analysis identifies four distinct types of consolidation happening in the market:

The Reshuffling of the Global 200

The current wave of mergers is set to redraw the global legal rankings significantly. Three merged firms are expected to be in the Global top 20 by gross revenue:

The Ashurst / Perkins Coie merger is expected to produce the largest gains in gross revenue (+92%).

Beyond the headline movers, Womble Bond Dickinson and FBT / Gibbons are also projected to climb approximately 30 positions each in the global rankings.

Not every firm growing its headcount is doing so through M&A. When Pirical analysed headcount growth across global law firms from January 2025 to February 2026, 70% of the top growers had done so through merger activity.

However, in this timeframe, three firms demonstrated that meaningful organic growth remains achievable:

For firms considering M&A as a growth strategy, one data point from Pirical's internal research is worth keeping front of mind: mergers have historically triggered an average partner headcount loss of around 6% from the point of announcement to completion.

This is not a reason to avoid mergers, but it is a reason to plan carefully, particularly around partner retention and communication during the transition period.