Kirkland & Ellis has dethroned Latham & Watkins as the world's largest law firm by gross revenue after growing its top line by 19% to $3.165bn in 2017, according to preliminary data and analysis by ALM.

Latham boosted gross revenue by 8.5% in 2017 to $3.064bn, about $100m shy of Kirkland's new record. The two firms are the first in history to cross the $3bn threshold.

Kirkland also saw its profits per equity partner (PEP) rise nearly 15% last year to $4.7m, a number topped by only two firms in the last Am Law 100 – Wachtell Lipton Rosen & Katz and Quinn Emanuel Urquhart & Sullivan. Both those firms achieved PEP of more than $5m for 2016.

The firm's London office, which has been growing aggressively in recent years, is understood to account for roughly 10% – about $316.5m (£257m) – of global revenue.

A main driver of Kirkland's growth was its significant increase in headcount, which rose 13.5% to 1,997 lawyers. Even still, the firm's premium practice groups, including litigation, private equity, public M&A and restructuring were able to keep its staff busier than in years past, as revenue per lawyer (RPL) rose 5.2% to $1.585m.

The firm declined to comment on its financial performance in 2017.

For a firm that has not engaged in a major merger – Kirkland added 17 lawyers through its acquisition of elite appellate boutique Bancroft in 2016 – the Chicago-based legal giant has been on a nearly unparalleled trajectory during the past five years.

Since crossing the $2bn mark in 2013, Kirkland's gross revenue has now grown 57%. Its headcount during that span has grown 28% and its PEP has surged 43%. The firm's RPL has increased, on average, 4.4% per year dating back to 2013. (Kirkland, which a year ago changed its framework for allocating equity partner profits, is known for having a large class of non-equity partners.)

Notably, the firm, led since early 2010 by Chicago-based corporate lawyer Jeffrey Hammes, has invested in some of the highest-priced geographies and practice groups.

Kirkland's fastest-growing offices include London, which has grown 61% since 2013 to 189 lawyers last year; New York, where headcount is up 42% during the past five years to 503 lawyers; San Francisco, up 36% since 2013 to 126 lawyers; and Houston, where the firm now has 107 lawyers since setting up shop in 2014.

The firm's decade-long transformation into a transactional powerhouse continued with one of its strongest years in private equity and public company M&A work. Kirkland's M&A team ranked fourth by the value of the deals it advised on in 2017, according to data compiled by Mergermarket. Kirkland also advised on more transactions (489), than any other firm, and saw the largest increase in the value of the deals it advised on from the previous year (up 63.5% in 2017 to $432bn).

Some of the firm's biggest public M&A deals included advising Mead Johnson on its $17.9bn acquisition by Reckitt Benckiser and Equity One on its $15.6bn stock-for-stock merger with Regency Centers.

In the private equity market, where Kirkland has long been a top player, the firm handled almost twice the number of deals (304) than its closest competitor, Latham (159), according to Mergermarket. Kirkland also led on the value of those deals, at $131.6bn – up 12% from the prior year.

Kirkland's private equity practice was bolstered with the opening of a Boston office, where it has since recruited well-known private equity partners from firms with well-established practices in the city, such as Choate Hall & Stewart, McDermott Will & Emery and Ropes & Gray.

The firm's vaunted restructuring practice also had another solid year, representing the debtor in three of the four largest Chapter 11 bankruptcies filed in 2017, according to BankrtuptcyData, which tracks bankruptcy filings. That work included representing deep water drilling firm Seadrill, struggling retailer Toys R Us and telecoms company Avaya.

Kirkland's two-plus-year representation of gaming giant Caesars Entertainment also came to an end last year, with the firm earning more than $70m in fees from that Chapter 11 case alone.

On the litigation front, Kirkland argued seven cases in front of the US Supreme Court, and helped clients to 34 victories at trial and 93 appellate wins. The results were propelled by a stellar year from James Hurst, a high-profile lateral hire from Winston & Strawn in late 2014, who won six cases at trial.

Kirkland was again aggressive on the lateral hiring front last year.

In August, a five-partner team on three continents came to Kirkland from Ropes & Gray, led by the latter's former global anti-corruption and international risks co-chair Asheesh Goel in Chicago and New York-based securities and futures enforcement co-head Zachary Brez. Several other Ropes & Gray lawyers subsequently joined Kirkland following that move.

In December, Freshfields Bruckhaus Deringer private equity heavyweight David Higgins joined as co-managing partner of the firm's London office in a reported $10m-a-year deal.

Kirkland made another splash in the lateral market at year's end by bringing aboard a team of lawyers from Debevoise & Plimpton in New York led by Erica Berthou, the former global head of the investment management and funds group at Debevoise, and Jordan Murray, a former deputy corporate chair at the firm.

Kirkland has set itself up for another growth year after starting 2018 with a slew of lateral hires, including hiring its third partner from Cravath Swaine & Moore in M&A expert Eric Schiele in New York, as well as Jennifer Perkins, a former global co-chair of Latham's private equity practice in the city.