Private equity has spent the past decade finding new sectors to penetrate. It has moved into healthcare, infrastructure, accountancy, and most recently the legal industry. Law firms have long been one of the few remaining corners of professional services genuinely resistant to outside investment, protected by ethics rules, partnership culture, and the reluctance of highly paid partners to dilute their annual profit share. That resistance is beginning to crack. The question is whether the crack becomes a flood or stays a trickle.

Key figures: Mourant stake sold: 27% to MML · Mourant revenue: above £127mn · Appleby investor shortlist: fewer than 10 · Top partner pay at major firms: more than $20mn a year · Completed UK and offshore deals: Mourant, Walkers, Northridge Law

The Structure That Changes Everything

US ethics rules prohibit non-lawyers from owning law firms directly, a restriction that has kept private equity out of Big Law for decades while buyout groups moved freely into accountancy and consulting. The management services organisation structure offers a way around this. It splits the firm into two entities: a lawyer-owned practice that provides legal advice, and a separate MSO that handles administrative functions, technology, intellectual property, and back-office operations. Private equity invests in the MSO, not the law firm itself, and the law firm pays a fee to the MSO for its services.1

Management Services Organisation (MSO): A legal structure that separates a law firm's legal work from its administrative and business functions. Non-lawyers can invest in the non-legal entity, circumventing US ethics rules that prohibit outside ownership of law firms directly.

Buyout groups have already used the MSO model to circumvent similar restrictions on ownership of medical practices and accountancy firms, and some smaller US firms, including personal injury specialists and start-ups, have adopted it too.2 What remains untested is its application at the top of the market, where the sums, the reputations and the partner economics are of an entirely different order.

The deeper resistance is cultural rather than regulatory. Lawyers are more attached to the traditional partnership model than accountants have proved to be, and are accustomed to taking home a firm's entire profit pool each year rather than reinvesting it in the business.3 An industry that distributes everything it earns has no obvious use for a balance sheet, and therefore no obvious use for an investor.

The Deals Already Done

Offshore firms, unburdened by US ethics rules, have moved first. Mourant, the Jersey-headquartered firm advising on offshore jurisdictions including the British Virgin Islands, has sold a 27 per cent stake to private equity investor MML, becoming the first of the so-called offshore magic circle firms to bring in private equity investment at group level.4 The firm ran its own equity raise alongside the deal, allowing its 60 shareholders to co-invest, and the pool was oversubscribed. Chief executive Jonathan Rigby framed it as a growth transaction rather than an exit: "This is not a deal where people are cashing out", he said, describing partners as putting further skin in the game.

Two details matter more than the headline percentage. Mourant employs around 1,000 staff but only 260 lawyers, the rest sitting in governance and consulting arms, and its revenue would place it inside the UK top 50 by turnover.5 It is, in other words, substantially a professional services group with a law firm attached, which is part of why a group-level deal was possible at all. Its owner-managers co-invested alongside MML and retain control of the group, while ownership of the separate law firm partnerships stays with locally qualified partners. Even offshore, where no ethics rule compelled it, the deal was structured to ring-fence the law firm.

Notably, the transaction carries no lock-in for partners and no clawback provisions, the Financial Times reported. For an industry whose central anxiety about outside capital is that talent will simply walk, the one completed group-level deal was structured without either mechanism to stop them.

Appleby, the offshore firm once at the centre of the Paradise Papers leak, is separately exploring a stake sale, with a shortlist of fewer than ten potential investors drawn up. Its parent is a limited liability company with a small group of shareholders, so any deal would need fewer approvals than at most large firms. That has not translated into speed: were a sale to proceed, it would be unlikely to complete before next year.3 Walkers, another offshore rival, agreed a deal with Vitruvian Partners in December to co-invest in its non-legal corporate services arm.6 A UK sports law boutique, Northridge Law, completed a minority investment from San Francisco's Cordillera Investment Partners in March.7

This is not a deal where people are cashing out.

Jonathan Rigby, Chief Executive, Mourant.

The UK and offshore markets are therefore already moving. The US is where the structural hesitation remains most acute.

The Big Law Impasse

Several prominent US firms have held exploratory conversations, though none has moved beyond them. Quinn Emanuel, which promotes itself as the world's most feared law firm, has spoken to investment bank Guggenheim Securities about what private investment might involve, while cautioning that no decision has been taken, no sale process has begun, and the work amounts to research. Proskauer has met at least one private equity group, and White & Case has a group of senior lawyers examining the structure.1

Paul Weiss executives met New Mountain Capital, a private equity group with $60bn under management, at the investor's request in New York. The firm has since been explicit that it listened to a couple of pitches some months ago at the request of firms it has business relationships with, that there have been no follow-up meetings, and that this is not something it is currently pursuing.2 McDermott Will & Schulte, first reported as exploring a deal in November, has continued meeting potential investors and advisers but remains far from a decision, and Cohen & Gresser has also said it is exploring outside investment.

The dynamic was captured precisely by one adviser specialising in MSO structures, speaking to the Financial Times: "Everyone is interested, but everyone wants to go second."

Everyone is interested, but everyone wants to go second.

An adviser specialising in MSO structures, speaking to the Financial Times.

That line explains the current impasse better than any amount of due diligence, but the uncertainty is narrower than it first appears. The structure itself has been road-tested, in medicine, in accountancy, and at the smaller end of the American legal market. What has not been tested is whether a firm of genuine stature can adopt it without the adoption itself becoming the story. The question elite firms are weighing is therefore less whether the model works than whether using it would look like an admission that they needed the money. The firms most capable of absorbing that risk are also the ones with the most reputation to lose, which is precisely why each would rather read about it happening to someone else first.

The size of that waiting group is itself the story. One attorney whose practice structures MSO deals told the Financial Times that her firm had spoken to half the Am Law 100, but that a far smaller group was actively exploring taking outside capital. Her test for those that were is a blunt one: every firm needs an answer to what it intends to do with the money, and without one that crystallises long-term benefit, it probably should not be doing the deal.

The concerns are concrete. Top partners can now take home more than $20mn a year, a figure driven up by US firms investing heavily in markets such as London and bidding aggressively for talent, which makes investors correspondingly vulnerable to departures. Some leaders fear the move would be read as older partners cashing out at the expense of younger generations. Others worry less about money than about control, specifically that lawyers would lose authority over how the firm allocates its own resources. And a powerful partner who dislikes the new ownership structure has options, most obviously walking out and taking their clients with them.

Two abandoned approaches suggest the hesitation is not merely rhetorical. MML held talks with UK firm Foot Anstey this year that have since ended, and private equity firm Synova spoke to Appleby but is not pursuing an investment, both according to the Financial Times.

The terms themselves remain unsettled. Burford Capital, whose main business is litigation finance, has pitched itself to Big Law as a hands-off minority investor and floated joining a consortium alongside a private equity buyer. Fortress Investment Group has suggested large firms could establish an MSO and sell debt rather than equity, the paper reported. These are materially different propositions, and the absence of a settled model is part of what firms are waiting on.

The AI Complication

Layered over the structural hesitation is the AI disruption question. Some investors are explicitly wary of law firm investments because AI threatens to automate significant portions of legal work, eroding the billing hours that underpin the business model, and uncertainty about that disruption has complicated deals across the sector. The concern is not abstract. AI tools already handle document review, contract analysis, and legal research functions that previously required junior associate time. If those functions are automated, the revenue base supporting the firm's valuation shrinks, and the investment case weakens accordingly.

MML's counter-argument on the Mourant deal is that specialist complexity provides a durable moat. The partner who led the deal argued that the firm's broad footprint and specialist areas made AI more of an opportunity than a risk.4 That argument may hold for niche offshore firms. It is less obviously true for large US generalist practices whose revenues depend partly on volume work that AI is already beginning to displace.

Where This Goes

The offshore and UK markets have already passed the tipping point. Mourant, Walkers, Appleby, and Northridge Law represent different points on the same trajectory, and the direction of travel is clear. An advisory market has formed around the trade: Dejonghe & Morley, the consultancy that advised Mourant, was launched in 2025 by two former magic circle leaders specifically to broker these deals.8 For those firms, the question is not whether private equity enters the legal sector but how the model evolves once it is established.

The US Big Law question is genuinely uncertain in a way the offshore question is not. The most likely near-term path is that a mid-sized US firm, large enough to attract meaningful interest but not so large that reputational and talent risk becomes existential, completes the first MSO deal and absorbs the regulatory and cultural consequences. If that goes smoothly, the firms currently sitting on the fence will move quickly. If it produces a partner exodus or a regulatory challenge, the hesitation hardens into something more permanent.

The irony is that the same firms paying enormous legal fees to Big Law are the private equity groups now circling it as an investment target. Whether the motive is genuine belief in law firm growth potential, a desire for exposure to one of the few remaining highly profitable professional services sectors that private equity does not own, or simply the appeal of getting some return on the fees they have been paying for decades, the direction of interest is consistent. The legal industry's long immunity to outside capital is ending. The terms on which that ending plays out remain, for now, an open question.

Footnotes

  1. Private Equity Wire, Major US law firms explore PE investment through alternative ownership structures (opens in a new tab), 6th August 2026. 2

  2. Financial Times, Biggest US law firms explore selling stakes to private equity (opens in a new tab), 6th August 2026. 2

  3. Financial Times, Paradise Papers law firm explores private equity sale (opens in a new tab), 5th August 2026. 2

  4. Financial Times, Offshore firm Mourant sells stake in private equity rush for legal deals (opens in a new tab), 4th August 2026. 2

  5. Global Legal Post, Mourant takes private equity investment to fund international expansion, AI investment (opens in a new tab), 4th August 2026.

  6. Cayman Compass, Mourant deal demonstrates investor interest in law firms (opens in a new tab), 6th August 2026.

  7. Legal Business, Top sports boutique Northridge becomes latest firm to score private equity investment (opens in a new tab), 31st March 2026.

  8. Legal Futures, Top offshore business takes minority private equity investment (opens in a new tab), 5th August 2026.