Merger control in United States

Arnold & Porter

Arnold & Porter continues to be a top-tier destination practice for business-critical mergers with a significant public profile, with the team regularly called upon as specialist antitrust counsel by global household-name businesses including AT&T, Cargill, and Sony for DOJ and FTC clearance proceedings, investigations and litigation, as well as multijurisdictional merger approvals. The Washington DC-based team is led by the vastly experienced Debbie Feinstein, who served as Director of the FTC Bureau of Competition, and maintains her record in high-level merger clearances, advising AT&T on the spin-off of WarnerMedia to its shareholders and the merger of the WarnerMedia business with Discovery, alongside Jonathan Gleklen , who specializes in high tech and network industry mergers. Michael B. Bernstein is advising Kroger on its $24.6bn proposed merger with Albertsons, and also acts for a number of other major public and private companies across industries, while Matthew Tabas is noted for his expertise in antitrust litigation, including representing clients against DOJ and FTC merger action.

Practice head(s):

Debbie Feinstein; Jonathan Gleklen

Other key lawyers:

Michael B. Bernstein; Matthew Tabas

Key clients





Boston Scientific


Cargill and Continental Grain






Thermo Fisher

Work highlights

  • Represented Sony in its $3.6 billion acquisitions of games software developer, Bungie.
  • Represented Kroger in its proposed $24.6 billion acquisition of grocery company, Albertsons Companies.
  • Represented AT&T in the spin-off of WarnerMedia to its shareholders and the merger of the WarnerMedia business with Discovery.

Cleary Gottlieb Steen & Hamilton

The ‘premier merger control practice‘ at Cleary Gottlieb Steen & Hamilton combines a prolific flow of HSR filings for major international businesses and private equity investors with standout work on contentious merger-related investigations and litigation brought by the DOJ, FTC, and state attorneys general, as well as international antitrust enforcers. The firm handles work in a wide range of regulated industries, with notable involvements in tech and healthcare on behalf of the likes of Broadcom and Change Healthcare, and is also able to point to a successful record in merger challenges against the government, evidenced by co-head Jeremy Calsyn  and Dave Gelfand‘s victory on behalf of Juul Labs in the FTC’s case against its investment from Altria Group. Leah Brannon  also co-heads the team, focusing on global merger approvals, while in San Francisco, George Cary is vastly experienced and remains active on major mandates, including Broadcom’s $61bn acquisition of VMware, and Brian Byrne , active between San Francisco and Washington DC, is another active team member. Elaine Ewing has handled strategic clearances for major clients such as Google and Coca-Cola, while former Bureau of Competition head Bruce Hoffman advises on innovative merger issues, including music industry portfolio sales. Daniel Culley continues to be a key contributor across merger filings, investigations, and litigation. Lawyers are in Washington DC unless otherwise stated.

Practice head(s):

Leah Brannon; Jeremy Calsyn

Other key lawyers:

George Cary; Bruce Hoffman; Brian Byrne; Elaine Ewing; David Gelfand; Daniel Culley


‘Cleary has a premier US merger control practice. Their team is comprised of people who have deep experience in all areas of antitrust, including complex mergers at both major agencies (FTC/DOJ). The senior lawyers in the group also have strong litigation experience, enabling them to carry a merger through not only the investigation stage, but also through any courtroom challenge if/when that arises. They are the go-to firm on the hardest deals that raise the most complex issues. They have excellent credibility and relationships with government lawyers, and are highly respected at the agencies and throughout the bar.’

‘Dave Gelfand – premier merger lawyer and litigator. The go-to person for bet the company litigation on mergers. Has done an incredible job mentoring and building a strong bench for the firm. Jeremy Calsyn – brilliant lawyer, incredibly hard working, tenacious, creative, and great relationships and credibility at DOJ and FTC. Would trust him with any deal (or any antitrust matter). George Cary – With Mark Leddy, helped build the practice and remains a force in the bar and in the firm. Great strategist and economic mind. Brian Byrne – Great lawyer, knows his clients’ businesses extremely well, allowing him to be a powerful advocate for them and to come up with creative solutions to navigate complicated regulatory waters. Elaine Ewing – Super smart, great lawyer, with a depth of experience that is hard to match at her level of seniority. A rising star in the group.’

‘Very practical application of agency experience that translates into what companies need.’

Key clients

Broadcom Inc.

T-Mobile USA

Korean Air

Applied Materials

Western Digital


JUUL Labs Inc.

The Coca-Cola Company

Fresenius Medical Care North America


Work highlights

  • Representing Broadcom Inc. in its proposed acquisition of VMware, Inc.
  • Representing JUUL Labs, Inc. (JLI) on the antitrust aspects of a $12.8 billion investment by Altria Group in JLI and in defeating the FTC in litigation before the FTC Administrative Law Judge to unwind the transaction.
  • Representing Google on several deals including its $5.4 billion acquisition of Mandiant; its $1.3 billion all-cash acquisition of Raxium; and its $500 million acquisition of Siemplify.

Latham & Watkins LLP

Latham & Watkins LLP remains active on complex, business-critical merger mandates for blue-chip clients, and enjoyed considerable success in contested mergers in 2022, most notably representing US Sugar against the DOJ’s challenge to its acquisition of Imperial Sugar, and advising Illumina on the multi-jurisdictional investigations into its acquisition of GRAIL. The team, which has a strong presence in Washington DC and the West Coast, was strengthened by the 2022 arrival of Katherine Rocco, a prolific merger counsel who has expanded the firm’s antitrust work in New York, and DC-based Makan Delrahim, formerly Assistant Attorney General for Antitrust, reinforcing the firm’s DOJ and FTC expertise. As well as handling major US clearances, related investigations, and litigation, the firm also leverages its global base, particularly in Paris and Brussels, to advise on multi-agency approvals across jurisdictions. The team is led by global antitrust chair Amanda Reeves  in DC, who took the lead on the US Sugar clearance, and Bay Area-based vice chair Belinda Lee , while DC-based Michael G. Egge is a vastly experienced figure with a track record in complex clearances, most notably representing Illumina in the GRAIL deal. Also in DC, Farrell J. Malone  is noted for his cross-border expertise, while Bay Area-based Kelly Fayne continues to expand her profile in the market, notably working closely with Reeves on MGM’s $8.45bn acquisition by Amazon.

Practice head(s):

Amanda Reeves; Belinda Lee

Other key lawyers:

Michael G. Egge; Katherine Rocco; Kelly Fayne; Farrell J. Malone; Makan Delrahim; Jason Cruise; Lindsay Champlin; Elise Nelson


‘The merger control team has been a key strategic partner to us in our evaluation of mergers – their likelihood of success and how to be proactive in ensuring our internal documents serve us in this process. The are especially strong in understanding our business and their ability to express their merger assessments in a consistent way from deal to deal.’

‘I value their strategic partnership – they know who are executives are, how they work, the type of materials they find helpful, how we want to understand risk, and how to be proactive in telling us about the external environment. Amanda Reeves is my trusted partner in any tricky antitrust situations.’

Key clients

United States Sugar Corporation


American Airlines


MGM Holdings, Inc.


Energy Transfer

Nestle USA, Inc.

Cerner Corporation

EP Energy


Frontier Airlines

Paper Excellence

The Carlyle Group

Tower Semiconductor

HRA Pharma

Work highlights

  • Defeated the DOJ’s challenge to U.S. Sugar’s acquisition of Imperial Sugar.
  • Advised Illumina on its US$8 billion purchase of GRAIL.
  • Obtained US antitrust clearance for global communications company Viasat’s acquisition of Inmarsat.

Skadden, Arps, Slate, Meagher & Flom LLP

Skadden, Arps, Slate, Meagher & Flom LLP advises a diverse global client base on domestic and international merger clearances, as well as representing them in DOJ and FTC investigations arising from proposed mergers and high-stakes litigation, regularly collaborating with the firm’s active M&A team and global network on multijurisdictional mandates. The firm continues to be active on high-profile tech mandates, notably representing Activision in its proposed acquisition by Microsoft, and Abode in its $20bn acquisition of Figma, as well as handling work in other highly scrutinized sectors such as financial services, transport, and sports. Global antitrust and competition group leader Steven Sunshine is a go-to for business-critical mergers, handling HSR filings, government investigations, and litigation for top-level clients in a wide range of industries. Tara Reinhart and Karen Lent lead the firm’s antitrust team in DC and New York respectively, while New York-based Boris Bershteyn is a key team member, specializing in contentious merger mandates.

Practice head(s):

Steven Sunshine; Tara Reinhart; Karen Lent

Other key lawyers:

Boris Bershteyn

Work highlights

Weil, Gotshal & Manges LLP

Weil, Gotshal & Manges LLP remains a sought-after destination practice for business-critical, complex M&A approvals, representing major global clients throughout highly scrutinized and contentious merger proceedings by the FTC, DOJ, and international regulatory authorities, working in concert with its growing European presence on international deals. Particularly strong in the tech and gaming spaces, the firm is advising Microsoft on its high-profile acquisition of Activision Blizzard, which is facing a FTC challenge, as well as representing Meta in its proposed $400m acquisition of Within Unlimited, while other sector strengths include retail and healthcare. Global antitrust head Steven Newborn is a former head of Mergers I at the FTC, and continues to handle a wide range of global merger approvals, while Brianne Kucerik, now co-head of US antitrust, is also highly active on contentious multi-jurisdictional merger cases, particularly within the gaming industry. Fellow co-heads Jeffrey Perry and and Michael Moiseyev are also former FTC Merger Division heads, furthering the team’s agency expertise, and Jeff White is noted for his broad practice, advising major companies and private equity clients throughout the merger process, including investigations and litigation. Megan Granger has bolstered her reputation within the space, playing key roles on the Meta and Microsoft deals along Moiseyev. All lawyers mentioned are in Washington DC.

Practice head(s):

Steven Newborn

Other key lawyers:

Brianne Kucerik; Jeffrey Perry; Jeff White; Mike Moiseyev; John Scribner; Megan Granger


‘Practical, knowledgeable, personable, creative and extremely hard working. A pleasure to work with all of the team.’

‘Megan Granger – no one works harder than Megan, smart and sensible. A pleasure to deal with. Steve Newborn – no nonsense and practical. Whipsmart and knows the industry and deals inside out.’

Key clients

Meta Platforms

MGM Resorts International

Microsoft Corporation

Norfolk Southern

Alpek and ALFA subsidiary

Charles River Laboratories


Eli Lilly

Sherwin Williams

Booking Holdings

Neogen Corporation

Bio-Rad Laboratories

Johnson & Johnson

Walgreens Boots Alliance

Work highlights

  • Advising Microsoft Corporation on its $68.7 billion acquisition of Activision Blizzard.
  • Represented MGM Resorts International on various transactions including its $1.625 billion acquisition of the operations of The Cosmopolitan from Blackstone.
  • Represented Sanofi in numerous billion dollar transactions, including its $1.225 billion acquisition of Amunix Pharmaceuticals, Inc., a developer of immuno-oncology technologies.

Baker Botts L.L.P.

Baker Botts L.L.P. focuses on complex, high-stakes merger clearance processes, advising major global businesses across industries such as energy, tech, and pharma on transactions facing scrutiny from the DOJ, FTC, and international antitrust agencies, from initial filing through to investigations and litigation. The firm offers strong contentious antitrust expertise, as well as broad multijurisdictional capabilities, regularly working with its teams in Europe on cross-border merger control mandates, and can call upon key senior agency experience in its senior team, with practice co-chair Maureen Ohlhausen a former chair of the FTC,  Taylor Owings having served as Chief of Staff at the DOJ Antitrust Division, and Mark Botti a former Section Chief at the DOJ. The team accordingly specializes in securing clearance for contested deals, including co-chair John Taladay ‘s successful closing of Mandiant’s acquisition by Alphabet, which faced a DOJ Second Request. In a key demonstration of the firm’s international expertise, Paul Cuomo  represented Liberty Latin America in its agreement with América Móvil to combine VTR and Claro Chile, a deal requiring approvals in multiple jurisdictions. Matthew Adler was promoted to partner in March 2022, and is noted for his work before the DOJ and FTC on regulated industry merger clearances. All lawyers mentioned are in Washington DC.

Practice head(s):

John Taladay; Maureen Ohlhausen

Other key lawyers:

Matthew Adler; Mark Botti; Paul Cuomo; James Kress; Taylor Owings


‘The team is made up of deep thinkers who understand the commercial drivers behind a deal. Very good knowledge of how the antitrust agencies are currently approaching issues and what arguments will resonate the most with them.’

‘Paul Cuomo is extremely savvy and commercially minded. He has a sharp mind and is a creative thinker.’

Key clients


Meta (Facebook)




QVC, Inc.

Celanese Corporation


Royal Dutch Shell

UnitedHealth Group Incorporated

Caterpillar Inc.


Georgia-Pacific LLC (GP Wood Products LLC)


CenterPoint Energy

Koninklijke Philips N.V.

ALDI, Inc.

HollyFrontier Corp

Sandoz, Inc.


Waste Management, Inc.

American Industrial Partners, LLC (AIP, LLC)

Conversant Wireless Licensing SARL

Sun Pharmaceuticals / Taro Pharmaceuticals

Westlake Chemical Corporation

Zydus Pharmaceutical, Inc.

Eagle Materials

Irico Display Devices Co., Ltd.

JSW Steel (USA) Inc. / JSW Steel USA Ohio, Inc.

Liberty Latin America Ltd.

Magellan Midstream Partners LP

Masco Corporation

McDermott International, Inc.

National Association of Boards of Pharmacy

Olin Corporation



SSW Partner LP

Raxium, Inc.

RWJBarnabas Health, Inc.

Envista Holdings Corporation

CMC Materials, Inc.

Energy Tranfer LP

Work highlights

  • Led the global merger clearance strategy and advocacy for Mandiant in its $5.4 billion acquisition by Alphabet, completing the second largest merger in Google’s history.
  • Represented Celanese Corporation in the multi-billion dollar acquisition of DuPont’s mobility and materials business.
  • Represented Liberty Latin America’s in multiple international transactions including an agreement between LLA and América Móvil S.A.B. de C.V. in the acquisition of América Móvil S.A.B. de C.V.’s operations in Panama.

Cravath, Swaine & Moore LLP

Cravath, Swaine & Moore LLP handles merger counselling mandates, both pre- and post-notification, for major corporates in the US and internationally, as well as representing clients throughout high-stakes regulatory actions and litigation relating to mergers, offering deep agency expertise and strong connections with the firm’s market-leading corporate practice. The team advises clients in a wide range of industries, and continues to see success in clearing deals in industries facing significant regulatory scrutiny, including a high-profile victory for Illumina against the FTC challenge to its acquisition by GRAIL, a standout development for practice head Christine Varney , a ‘world class strategist’ and former FTC Commissioner. Elsewhere in the team, Maggie Segall is praised by clients as a ‘superstar’ and is prolific in securing clearances for high-value mergers, as well as advising clients on government investigations, while former FTC official Daniel Zach has great experience of merger litigation and successfully represented Louis Dreyfus Company against the DOJ’s challenge to the sale of subsidiary Imperial Sugar to US Sugar. Former FTC Commissioner Noah Joshua Phillips joined the firm as co-head of the antitrust practice in late 2022, expanding its regulatory expertise and resident in the firm’s Washington DC office. Lawyers are in New York unless otherwise stated.

Practice head(s):

Christine Varney

Other key lawyers:

Maggie Segall; Daniel Zach; Noah Joshua Phillips


‘They have built out a team of AT experts and US Agency experts, including two former FTC Commissioners, one of whom was also AAG for antitrust. They are a set of diverse men and women.’

‘Christine Varney is a world-class strategist. And Maggie Segal is a superstar.’

Key clients

AerCap Holdings N.V.

Afterpay Limited

Atlas Air Worldwide Holdings, Inc.

Global Blood Therapeutics, Inc.

Illumina, Inc.

Louis Dreyfus Company, LLC

Micro Focus International plc

National Grid plc


Viatris Inc.

Work highlights

  • Sucessfully represented Illumina in rejecting the FTC’s high-profile challenge to the company’s $8 billion acquisition of GRAIL.
  • Represented Louis Dreyfus Company and its subsidiary Imperial Sugar, defeating the DOJ’s attempt to block Louis Dreyfus’s sale of Imperial Sugar to U.S. Sugar.
  • Represented AerCap Holdings N.V. on antitrust issues in connection with its $30 billion acquisition of GE Capital Aviation Services from General Electric.

Davis Polk & Wardwell LLP

Routinely involved in complex, high-profile clearances for business-critical domestic and cross-border deals, the team at Davis Polk & Wardwell LLP is able to handle DOJ and FTC processes for mergers and joint ventures, as well as international agency approvals, investigations, and litigation relating to proposed mergers. The firm has standout strength in key sectors such as pharma, oil and gas, telecoms, and financial services, and is also noted for its representation of private challengers to transactions before both US and global agencies. Arthur Burke leads the team, and is experienced in both HSR filings and contested merger approval processes for deals in the tech and media space, while Ronan Harty continues to enjoy significant success in major deal clearances, closing IHS Markit’s $44bn merger with S&P Global in February 2022, a deal which also saw a significant role for counsel and former FTC official Suzanne Munck af Rosenschold, noted for her expertise in matters concerning the intersection of antitrust and intellectual property, particularly in the life sciences and pharma industries. Jesse Solomon in Washington DC has further bolstered his reputation for handling high-stakes international mergers, co-ordinating global strategy and succcessfully defending proposed transactions before the DOJ and FTC, with a major victory in 2022 being his advice to ICM Partners on its acquisition by Creative Artists Agency, which faced a significant review by the DOJ. All lawyers are in New York unless otherwise stated.

Practice head(s):

Arthur Burke

Other key lawyers:

Ronan Harty; Jesse Solomon; Suzanne Munck af Rosenschold; Howard Shelanksi

Work highlights

Jones Day

With a broad US-wide and global platform, Jones Day advises clients throughout complex domestic and cross-border transactions in key industries including energy, financial services, pharma, and healthcare, with capabilities in domestic and international merger filings, DOJ and FTC investigations, including Second Request processes, and merger-related litigation. The practice is led by Craig Waldman, who has worked in the FTC’s Mergers I division and specializes in the tech, financial services, and transport sectors, while Michael Gleason advised Parker-Hennefin on its $8bn cross-border acquisition of Meggitt, a standout international mandate for the team. Ryan Thomas  is noted for his expertise across deals in a wide range of industries, encompassing contentious investigations and global approvals. In Houston, Bruce McDonald has litigation experience and regularly handles transactions in the energy, infrastructure, and transport sectors. Aimee DeFilippo continues to bolster her reputation on complex deals, advising Valmet on its statutory merger with Neles. Lawyers are in Washington DC unless otherwise stated.

Practice head(s):

Craig Waldman

Other key lawyers:

Ryan Thomas; Bruce McDonald; Michael Gleason; Michael Knight; Aimee DeFillippo


‘Jones Day has a rare combination of mastery of law, specific industry knowledge that is indispensable particularly in complex regulated industries, and ability to think like business people.’

‘Bruce McDonald- he distills sophisticated legal expertise, industry knowledge, and judgment into very practical, easy to use business advice. Business people within the organization readily understood it which made my job as an in-house attorney much easier.’

Key clients

Avient Corporation

Cargill, Inc.

Cricket Health

Koch Industries

LCMC Health

Parker-Hannifin Corporation

Skyworks Solutions, Inc.

The Boeing Company

The Riverside Company

Valmet Oyj

Work highlights

  • Advised Parker-Hannifin Corporation on its USD 8.8 billion acquisition of Meggitt.
  • Represented Cricket Health in its USD 2.4 billion three-way merger with Fresenius Health Partners and InterWell Health to establish a state-of-the-art value-based kidney-care provider.
  • Represented Valmet Oyj in its statutory merger with Neles Corporation.

Kirkland & Ellis LLP

Kirkland & Ellis LLP advises public and private companies, including major names such as Bain Capital, KKR, and Celanese on merger clearance for M&A and private equity transactions, combining a prolific record in HSR filings with strong capabilities across DOJ and FTC investigations, including Second Request proceedings, global approval processes, and antitrust litigation relating to mergers. The team has deep agency experience, with practice head Matthew Reilly, who is advising Celanese on its proposed $11 billion acquisition of Dupont’s Mobility & Materials business, having acted as assistant director of the FTC Mergers Division, and an expert in high-stakes merger trials across sectors such as pharma, telecoms, and defense. Andrea Murino, who held positions at the FTC and DOJ, focuses securing clearances from the agencies for major deals, including handling Second Requests. New York’s Ian John is a prolific advisor to major clients on complex cross-border transactions, while Marin Boney offers economics expertise and experience in analyzing joint ventures and vertical agreements alongside merger control capabilities. All lawyers are in Washington DC unless otherwise stated.

Practice head(s):

Matthew Reilly

Other key lawyers:

Marin Boney; Ian John; Andrea Murino

Key clients

Bain Capital

Celanese Corporation

Clayton, Dubilier & Rice

Cobham Group

Datto Holding Corp.




Nexstar Media Group

Nordic Capital

Norton LifeLock

Oracle Corporation

Prince International


UnitedHealth Group

Vestar Capital Partners

Warburg Pincus

Water Street Healthcare Partners

Welsh, Carson, Anderson & Stowe

Yale New Haven Health

Work highlights

Paul, Weiss, Rifkind, Wharton & Garrison LLP

Paul, Weiss, Rifkind, Wharton & Garrison LLP combines high-stakes merger clearance expertise with strong capabilities in regulatory investigations and merger-related litigation thanks to deep agency experience, bolstering its contentious antitrust expertise with the arrival of New York-based Katherine Forrest, an experienced litigator and former judge, from Cravath, Swaine & Moore LLP in late 2022. The team acts for major public companies in a variety of industries, as well as bulge-bracket private equity clients, combining a solid deal flow from the firm’s active transactional practices with regular destination instructions for business-critical strategic deals. Antitrust co-chair and former Acting Assistant Attorney General Andrew Finch is a key figure in the team, regularly advising the likes of Apollo and Mastercard on merger clearances, while Joshua Soven arrived from Wilson Sonsini Goodrich & Rosati in February 2022 and is noted for his expertise in regulated industry antitrust issues, particularly in the healthcare and tech fields. Aidan Synnott also co-chairs the antitrust team, and notably advised Continental Grain on the acquisition of Sanderson Farms. Kenneth Gallo is a key name, focusing on antitrust litigation, while Brette Tannenbaum continues to bolster her reputation in contentious mandates.  Lawyers are in Washington DC unless otherwise stated.

Practice head(s):

Andrew Finch

Other key lawyers:

Aidan Synnott; Joshua Soven; Ted Wells; Kenneth Gallo; Brad Karp; Brette Tannenbaum; Katherine Forrest

Work highlights

Simpson Thacher & Bartlett LLP

Simpson Thacher & Bartlett LLP leverages its strong profile within the private equity space, advising a number of major buyout funds on global antitrust filings and investigations, combining this work with a notable focus on complex public M&A approvals, offering deep agency experience on mandates facing Second Request investigations as well as antitrust lawsuits brought by the DOJ and FTC. The team is able to handle mergers in highly scrutinized industries, particularly healthcare, with Washington DC-based co-head Sara Razi successfully representing Change Healthcare in the DOJ challenge to its acquisition by UnitedHealth, as well as financial services. New York’s Peter Guryan co-heads the team and is a former Antitrust Division trial attorney, allowing him to handle contentious merger proceedings both domestically and internationally, and is particularly active on behalf of private equity-backed companies and funds. DC-based Preston Miller is an increasingly key team member, focusing heavily on merger review and playing a major role in the Change deal, with senior counsel Richard Jamgochian in New York also noted for his broad sector knowledge and work on antitrust risk analysis at the outset of deals.

Practice head(s):

Peter Guryan; Sara Razi

Other key lawyers:

Preston Miller; Richard Jamgochian


‘Simpson Thacher is an absolute leader in US, UK and EU competition law. They have real super stars in New York, Washington and London. They routinely work on the most difficult merger and commercial matters and investigations. They are always fast and efficient, never seeking to do unnecessary or ineffective work. They stay on top of key legal developments, are incredibly responsive and are a real go to firm.’

‘Peter Guryan: Peter is among the most underrated antitrust lawyers in the US (and most certainly in New York). He is calm, efficient, collaborative, extremely smart and the kind of advocate that you want in your corner. There isn’t a merger control matter that he can’t do or a fact scenario he hasn’t seen.’

‘Preston Miller is such a strong lawyer that partners from other firms routinely acknowledge the benefits of having him on the other side as someone who will be efficient, practical, friendly and able to lead a very strong case. He is definitely going to be a leader in the antitrust bar.’

‘Rick Jamgochian: Rick is a master organizer. He is able to manage complex and large merger investigations. He is calm and never loses his cool. He is a fantastic lawyer and team player.

Key clients


Buckeye Partners, L.P.

Change Healthcare

CSL Limited

Ferro Corporation

Garda World Security Corporation

HCA Healthcare, Inc.


The NPD Group

ODP Corporation

U.S. Bancorp

Work highlights

  • Representing Change Healthcare in its $13.8 billion acquisition by UnitedHealth Group, including representing Change Healthcare in the highly publicized merger trial in which UnitedHealth and Change were victorious over the Department of Justice.
  • Representing PPD Inc. in its $17.4bn acquisition by Thermo Fisher Scientific Inc.
  • Representing Cosmopolitan of Las Vegas and Blackstone Real Estate Partners VII L.P. in the $5.65bn sale of The Cosmopolitan.

White & Case LLP

White & Case LLP has a strong record in securing clearances for business-critical, global transactions, and is a destination practice for a number of high-profile deals, handling DOJ and FTC investigations, regulatory challenges, and multijurisdictional approvals. In a standout representation for practice head George Paul and highly-rated senior associate Heather Greenfield, the firm is acting for Albertsons in its $24bn merger with Krogers, a major deal in the supermarkets sector which is currently facing a FTC Second Request, while the practice has also expanded its work for major big tech clients including Twitter and Google, as well as remaining active in key sectors such as tech and software. Rebecca Farrington is a key name for FTC and DOJ merger investigations as well as cross-border mandates, and is representing Avast in its high-profile merger with Norton Life, a deal with US and UK elements, while Tamer Nagy was promoted to partner in January 2023 and specializes in Middle East-domiciled work. Anna Kertesz continues to offer agency expertise on contested mergers, and is a regular advisor to key clients such as Meta and Whatsapp. All lawyers are in Washington DC.

Practice head(s):

George Paul

Other key lawyers:

Rebecca Farrington; Tamer Nagy; Heather Greenfield; Anna Kertesz


‘Rebecca Farrington is bright, experienced, thorough, and a pleasure to work with. I recommend her highly!’

Heather Greenfield is a talented associate–poised, energetic, and smart. I think she has a bright future in front of her.

‘Tamer Nagy in DC is very knowledgeable and resourceful. Collaboration with their global team in EU, UK is great.’

‘Knowledgeable, with diversity and able to address merger control on a global basis Resourceful with a global team; also collaboration with partnered firms where they don’t have internal team. Able to address queries quickly. Well-equipped team, ready to react and provide advice.

‘Able to assemble large diverse teams. Strong bench of up and coming counsel. Practical and effective in providing legal guidance aligned with business objectives.’

‘Rebecca Farrington and Anna Kertesz are efficient, well versed in antitrust agency process, and effective in conveying practical guidance aligned with business realities and objectives.’

‘Very good merger control connections and ability in the Middle East.’

‘Tamer Nagy has a great knowledge of the emerging regulatory landscape in the Middle East and is a pleasure to work with.’

Key clients



Novasep Process SAS

GlobalWafers Co. Ltd

Smiths Group plc

Pilot Co.


Vox Media Holdings, Inc.

Viva Aerobús


Development Partners International

Kobalt Music

Work highlights

  • Represented Albertsons in its US$24.6 billion merger with Kroger.
  • Advised UK-based Avast on its US$8.6 billion merger in multiple jurisdictions with U.S.-based NortonLifeLock.
  • Advised Novasep Process SAS on a milestone antitrust approval of a FTC petition filed by Sartorius Stedim Biotech S.A. to acquire the chromatography equipment business of Novasep.

Debevoise & Plimpton LLP

Debevoise & Plimpton LLP advises clients on HSR filings alongside DOJ and FTC reviews of mergers and joint ventures, as well as offering strong capabilities in high-stakes merger litigation and accompanying antitrust investigations, and being able to secure multi-jurisdictional clearance for transactions in concert with foreign counsel and the firm’s global offices. Sector strengths for the firm include financial services, consumer good, pharma, and telecoms, with a large portfolio of high-profile clients featuring major names such as Albertsons, American Express, and Verizon. The practice is overseen by New York-based Michael Schaper , who has a successful record in private equity, Washington DC-based litigator Ted Hassi, and New York’s Erica Weisgerber, a specialist in financial services antitrust issues. Senior associate Leah Martin in DC has played a key role in merger clearances for top clients including Albertsons and CD&R.

Practice head(s):

Ted Hassi; Michael Schaper; Erica Weisgerber

Other key lawyers:

Leah Martin

Key clients

Albertsons Companies, Inc.

American Express

Armando Kellum

Artera Services, LLC

AVEVA Group plc

BTD Recovery Holdings 4, LLC

Carestream Dental

Clayton Dubilier & Rice and Portfolio Companies

Cornerstone Building Brands


DBS Bank Ltd.

Domtar Corporation

Dover Corporation

Elliott Management Corporation

Global Atlantic

Great American Outdoors Sports Group

Kindred Healthcare

Peabody Energy Corporation

Prudential Financial, Inc.


S&S Activewear

Sandoz, Inc.’s former CEO, Armando Kellum

Sun Life Financial

The Bank of Yokohama Ltd

Toyota Motor Sales, U.S.A. and Toyota Canada, Inc.

TPG Capital

Tractor Supply

Verizon Communications Inc.

Welsh, Carson Anderson & Stowe

Wilsonart International Holdings

Dechert LLP

Dechert LLP handles merger clearances for public companies, private equity funds, and their portfolio companies, combining work on HSR filings and joint venture approvals with notable litigation capabilities and regular roles representing third-party challengers to high-profile mergers in proceedings brought by the FTC and DOJ, as well as before international antitrust regulators and state attorneys general. The team has broad sector expertise, with notable involvements in the retail, healthcare, and energy industries, with practice co-head Mike Cowie  a go-to for contentious merger work in the life sciences and healthcare space, and a former FTC official alongside James A Fishkin , who has in-agency experience of merger trials. Steven Bizar  co-leads the team from Philadelphia, while Shari Ross Lahlou is noted for her expertise in investigations and merger-related litigation, and Rani Habash  continues to expand his reputation with regular work for major healthcare clients such as CVS Health and Aetna. The team was bolstered by the February 2023 arrival of the experienced Jay Jurata, a specialist in tech platforms deals, from Orrick, Herrington & Sutcliffe LLP. Lawyers are in Washington DC unless otherwise stated.

Practice head(s):

Mike Cowie; Steve Bizar

Other key lawyers:

James Fishkin; Shari Ross Lahlou; Rani Habash; Jay Jurata

Key clients


Court Square Capital

CVS Health

Henry Crown

DTE Energy

Diamonds Direct

Jacksons Food Stores

One Equity Partners

Work highlights

  • Represented Jacksons Food Storeson its purchase of 63 fuel outlets and convenience stores required as part of a FTC consent decree resolving competitive concerns related to 7-Eleven, Inc.’s US$21 billion acquisition of Speedway from Marathon Petroleum Corp.
  • Advising Court Square Capital Partners on its sale of Getaroom, a leading B2B hotel accommodations distributor, to Booking Holding.
  • Representing Ritchie Bros. Auctioneers in its agreement to acquire Euro Auctions.

Freshfields Bruckhaus Deringer LLP

Freshfields Bruckhaus Deringer LLP continued its growth in the United States with the arrival of Jamillia Ferris from Wilson Sonsini Goodrich & Rosati in September 2022, contributing significant agency experience of complex merger review processes, including both the DOJ and FTC. Alongside growth in its bench, the team also expanded its share of household-name clients, representing Google, Verizon, and eBay in new antitrust mandates during 2022. The team has experience in representing major domestic and global clients in US merger control proceedings, as well as co-ordinating global approvals in concert with its international offices, including in the UK and Europe, and representing clients facing regulatory action by agencies, encompassing investigations and litigation. Practice head Bruce McCulloch continues to be highly successful in merger mandates, notably representing Aerojet in its $4.4bn acquisition by Lockheed Martin, while Mary Lehner is also highly active, advising Cargill on its take-private of Sanderson Farms. Meghan Rissmiller  is another key team member, and is a regular antitrust counsel to major clients such as eBay, while Justin Stewart-Teitelbaum is noted for his work on complex merger investigations. All lawyers mentioned are in Washington DC.

Practice head(s):

Bruce McCulloch

Other key lawyers:

Mary Lehner; Jamillia Ferris; Meghan Rismiller; Justin Stewart-Teitelbaum; Jan Rybnicek


‘Freshfields really offers a seamless approach across jurisdictions. In the US, the recent growth of the practice through internal promotion and external hires ensures a great breadth and depth of expertise.’

‘Meghan Rissmiller is smart, hands-on and result-driven. Where other lawyers may theoreticize and appear aloof, she’ll get to the point and make it easy for business people to understand and engage. Tom Morgan’s background working on both sides of the Atlantic gives him a broad perspective and allows him to give clients profound advice on their multi-jurisdictional merger matters. He is great to work with, both detail-oriented and able to explain the big picture.’

‘Mary Lehner – An excellent strategic thinker who is not afraid to present the right solution even though it may present some costs. Practical advice to the business without being too technical. Justin Stewart-Teitelbaum – An excellent and practical lawyer who knows how to get things done. Keen insight into agency process. A real star in development.’

‘Great global firm.’

‘Jamillia Ferris was a great addition, given her experience and expertise.’

‘Meghan Rissmiller is an excellent attorney – thoughtful, understated and informed. She is always able to provide accurate market intel and has thus become a go-to resource for our firm.’

‘The merger control practice at FF is very solid team with knowledgeable partners and a wide group of good associates supporting the partners. This is important in cases of multi-jurisdictional activities where many filings at the same time will need to be made and coordinated. The team is technically strong, has good links with the EU institutions and works on a very coordinated basis internally with corporate colleagues, but also with a wide network of local counsel around the globe. They provide an all-in service, both on substance and on procedure.’

Key clients


Cargill, Inc.


Telefonaktiebolaget LM Ericsson

Stanley Black & Decker, Inc.


Massachusetts Institute of Technology (MIT)

United Airlines

Aerojet Rocketdyne

Axel Springer


AmerisourceBergen Corporation



General Dynamics


Work highlights

Fried, Frank, Harris, Shriver & Jacobson LLP

Fried, Frank, Harris, Shriver & Jacobson LLP advises public companies, private equity investors, and financial institutions on major cross-border merger approval processes, as well as handling US and international antitrust investigations into joint ventures and vertical agreements in a variety of industries. The team balances strong global transactional expertise with standout litigation capabilities, allowing it to represent clients through contentious proceedings and merger trials against federal enforcement bodies and state attorneys general, with Washington DC-based practice head Barry Nigro ‘well respected at both DOJ and FTC’. Nigro, formerly Principal Assistant Deputy Attorney General at the Antitrust Division, continued his successful record in major mergers, advising Standard General on an affiliate’s $8.6bn acquisition of TEGNA Inc, while Nathaniel Asker , also a prolific international merger counsel, is representing Permira as part of a consortium acquiring Zendesk in a $10.2bn take-private. Counsel Aleksandr Livshits has expertise in merger approvals and related investigations across industries such as pharma, retail, and tech. Richard Powers joined from the DOJ in September 2022, contributing significant experience of antitrust prosecution on the agency side and bolstering the team’s contentious capabilities. All lawyers mentioned are based in New York, unless otherwise stated.

Practice head(s):

Barry Nigro

Other key lawyers:

Nathaniel Asker; Aleksandr Livshits


‘Barry Nigro is one of the best M&A antitrust lawyers in the country, and well respected at both DOJ and FTC. Barry is excellent technically and analytically, but what makes him truly outstanding is his practicality and common sense approach.’

Key clients


Jacobs Engineering Group

Standard General L.P.

Goldman Sachs Asset Management

RedBird Capital Partners


Catalent, Inc.

Aerie Pharmaceuticals, Inc.

New Mountain Capital


Jacob Holm



AEA Investors

Work highlights

  • Advised a consortium of investors that included Permira and Hellman & Friedman, in the $10.2 billion all-cash take private of Zendesk.
  • Advised Standard General L.P., alongside an affiliate, in the affiliate’s $8.6 billion acquisition of TEGNA Inc.
  • Advised MasTec in its $1.1 billion acquisition of Infrastructure and Energy Alternatives, Inc.

Gibson, Dunn & Crutcher LLP

Gibson, Dunn & Crutcher LLP advises a global client base on merger clearances in the US and internationally, leveraging the firm’s global reach in multijurisdictional mandates involving multiple regulatory approvals and investigations by US, European, and UK antitrust authorities. The firm handles matters in a variety of industries, with key representations for the likes of LIV Golf, Apple, and Norvatis, and combines merger filing expertise with standout contentious capabilities, supporting clients throughout investigations and high-stakes litigation. The team is led by San Francisco’s Rachel Brass alongside former FTC Deputy Director Stephen Weissman, with Michael Perry, who has long-standing experience in DOJ and FTC merger proceedings, Scott Hammond, and Cynthia Richman other key names to note. Lawyers are in Washington DC unless otherwise stated.

Practice head(s):

Rachel Brass; Stephen Weissman

Other key lawyers:

Scott Hammond; Michael Perry; Cynthia Richmond

Key clients

LIV Golf



Merck & Co., Inc.

Jimmy John’s

Kraft and Mondelez

Smithfield Foods

Novartis AG


Panasonic Corporation and Panasonic Corporation of North America

Work highlights


Goodwin leverages its strength in key industry verticals across healthcare and life sciences, tech, and private equity, advising businesses and funds on strategic acquisitions, portfolio company mergers, and divestitures, with a strong record in both avoiding Second Requests from the DOJ and FTC as well as navigating investigations brought by regulatory authorities. The firm combines a prolific deal flow with involvement in high-profile, contentious merger clearances, notably advising iRobot on its acquisition by Amazon, and handling the antitrust elements of Nimbus Therapeutic’s defense of a hostile takeover attempt by Bristol Myers Squibb. The practice is led by Washington DC’s Andrew Lacy, who represents clients through the merger process, including litigation brought by the DOJ and FTC, alongside Arman Oruc, a life sciences antitrust specialist who divides his time between DC and Los Angeles. Also in DC, Paul Jin is noted for his HSR expertise.

Practice head(s):

Andrew Lacy; Arman Oruc

Other key lawyers:

Paul Jin


‘Very practical and solution-oriented. Seamless work across time zones. Realistic timelines.’

‘Great teamwork.’

‘The Goodwin team supported our acquisition. I found the Goodwin team extremely professional, knowledgeable, having an excellent process, and being very client oriented. Our timeline from term sheet to signing the deal was three weeks, which typically takes 2 months. This would have been impossible without the incredible dedication of the Goodwin team.’

Key clients

Bio Products Laboratory (BPL) and its shareholder, Tiancheng International Investment Limited (TII)

Checkmate Pharmaceuticals

Deliverr, Inc.

Explora Biolabs Holdings, Inc.

InterWell Health

iRobot Corp.

Lucid Holdings, LLC

Mimecast Limited

Nimbus Therapeutics

Trillium Therapeutics

Work highlights

  • Aadvising iRobot on all antitrust aspects of its proposed $1.7 billion acquisition by Amazon.
  • Represented Nimbus Therapeutics in its bet-the-company efforts to retain its crown jewel asset against a hostile attempt by Bristol-Myers Squibb (BMS) to acquire it.
  • Advised InterWell Health LLC in navigating an FTC Second Request investigation into its combination with Fresenius Health Partners and Cricket Health Inc., in which the three companies merged to create a value-based kidney care company valued at $2.4 billion.

Hogan Lovells US LLP

Offering a strong focus on regulated industries such as healthcare and tech, and a successful record in contentious merger cases, encompassing filings, investigations, and litigation, the team at Hogan Lovells US LLP represents major US and international clients before the DOJ, FTC, and global agencies in strategic mergers and joint ventures approval processes. The team offers considerable agency experience, with Edith Ramirez a former chair of the FTC and an expert in global merger clearances, while Charles Loughlin previously served as a trial counsel at the FTC and specializes in contested merger cases. Practice head Logan Breed  continues to be active on high-value, business-critical clearances across industries, and is representing Within in its proposed acquisition by Meta, which has been challenged by the FTC. Lauren E. Battaglia handles cross-border mergers, and is particularly active in the life sciences and biopharma spaces. All lawyers mentioned are in Washington DC.

Practice head(s):

Logan Breed

Other key lawyers:

Justin Bernick; Charles Loughlin; Edith Ramirez; Lauren E. Battaglia


‘Hogan has a strong merger control practice. They have a former FTC chair  and FTC head trial counsel, both of whom are sophisticated agency practitioners.’

‘I have worked mainly with Edith Ramirez and Chuck Loughlin, but also others on their team. We were co-counsel on a matter, and had a very good working relationship. Edith has great connections with senior people at the agency and insights on political issues driving commission activities. Chuck is much more of a straight up litigator than an agency merger lawyer, but he has litigated many mergers so he is very skilled in the area and knows the practice in these fast moving cases. They are both easy to work with.’

Key clients

Kustomer, Inc.

Meggitt PLC

Tops Market


United Health Group (UHG)


Within Unlimited



Work highlights

  • Advising Within on its proposed acquisition by Meta.
  • Advised UnitedHealth Group on the planned US$13bn merger of its Optum division with Change Healthcare.
  • Representing ASSA ABLOY in its proposed acquisition of the HHI division of Spectrum Brands for approximately US$4.3 billion.

Linklaters LLP

Linklaters LLP offers broad DOJ and FTC expertise to a wide range of global clients, with a particularly strong focus on strategic merger clearances in regulated industries such as healthcare, pharma, and financial services. Alongside domestic and international approval processes, the team also offers demonstrable expertise in contentious issues including regulatory investigations and litigation relating to contested mergers, and is able to handle emerging issues relating to foreign investment controls. Washington DC’s Antonia Sherman leads the team, and combines an active HSR practice with cross-border M&A experience, particularly in Latin American jurisdictions. Tom McGrath in New York specializes in life sciences and chemicals transactions, while counsel John Eichlin, also New York-based, has worked in Europe and Asia, and contributes standout multijurisdictional merger and foreign investment control capabilities, as well as global consumer protection issues relating to deals in diverse industries.

Practice head(s):

Antonia Sherman

Other key lawyers:

Tom McGrath; John Eichlin

Key clients

Bioceres Crop Solutions Corp





Novo Holdings

Quidel Corporation

Tate & Lyle

Work highlights

  • Represented Bioceres Crop Solutions Corp in connection with its US$236 million merger with Marrone Bio Innovations, Inc.
  • Advised Cerberus on several transactions, including Worldwide Flight Services’ (part of the Cerberus portfolio) acquisitions of Mercury Air Cargo and Pinnacle Logistics.
  • Advised Glencore on a number of transactions, including Glencore plc’s sale of Chemoil Terminals LLC to an investor group consisting of Davidson Kempner Capital Management, Pilot Travel Centers, and Intrepid Investment Management.

McDermott Will & Emery LLP

McDermott Will & Emery LLP is noted for its high-level specialist healthcare antitrust and FTC practices, combining a steady stream of HSR filings and merger approvals with standout capabilities in government merger investigations and litigation, also working regularly on transactions in the tech and defense sectors, among others. The team includes diverse merger and contentious antitrust experts, with practice head Raymond Jacobsen working on major US and international mandates in industries including defense, medical devices, and biotech, while former FTC Mergers II lawyer Joel Grosberg has a strong knowledge of FTC and DOJ merger processes, advising on acquisitions, sales, and joint ventures. Jon Dubrow is a prolific HSR counsel and also focuses on securing first-stage approvals for highly scrutinized deals, Gregory Heltzer stands out for his merger defense work, and Lisa Rumin has also seen success in defending mergers in the healthcare, pharma, and biotech against investigations by state and federal authorities. Chicago’s Stephen Wu  plays a key role in the firm’s health antitrust offering. All lawyers mentioned are in Washington DC unless otherwise stated.

Practice head(s):

Raymond Jacobsen

Other key lawyers:

Joel Grosberg; Jon Dubrow; Gregory Heltzer; Lesli Esposito; Lisa Rumin; Noah Feldman Greene; Stephen Wu

Key clients


Lockheed Martin

Martin Marietta Materials, Inc.

Cedars Sinai Health System

The Chartis Group

Care New England Health System

Geisinger Health

Work highlights

  • Represented PerkinElmer in the acquisition of BioLegend for US$5.25 billion.
  • Represented Lockheed Martin in connection with its US$5 billion acquisition of Aerojet Rocketdyne.
  • Represented Care New England Health System in its proposed US$920 million merger with Lifespan Health System.

Morgan, Lewis & Bockius LLP

Morgan, Lewis & Bockius LLP offers an active HSR-focused practice, advising a wide range of major companies in industries such as tech, defense, and life sciences, as well as private equity funds including Apollo and Digitalbridge, on pre-merger notifications for strategic acquisitions, as well as handling DOJ and FTC investigations and regulatory challenges. The team is noted for its cross-border capabilities, representing clients throughout the approval process for multijurisdictional deals, including its standout work for Perrigo on its $1.9bn acquisition of HRA Pharma, a deal requiring approval in multiple European jurisdictions, as well as facing a FTC Second Request investigation. The team is overseen by New York’s Harry Robins , an experienced transactional antitrust advisor and HSR specialist, with Washington DC-based Jonathan Rich specializing in cross-border merger approvals, while also in DC, Ryan Kantor is noted for his leading role in merger investigations.

Practice head(s):

Harry Robins

Other key lawyers:

Jonathan Rich; Ryan Kantor

Key clients



AP Moller Maersk



EQT Partners


Hitachi Metals

Intercontinental Exchange

Merck & Co. Inc.

Perrigo Company plc

Pfizer Inc.

Platinum Equity

Pacific Architects and Engineers


Realogy Holdings, Inc.,


Securus Technologies Inc.

Sumitomo Corporation

Sun Capital Partners Inc.



Zoetis Inc.

Work highlights

  • Advised Perrigo Company plc in its $2.1 billion acquisition of Hera SAS (HRA Pharma).
  • Representing Intercontinental Exchange, Inc. (ICE) as antitrust counsel in its proposed acquisition of Black Knight, Inc.
  • Represented DigitalBridge in its $11 billion acquisition of data center operator Switch Inc.

Morrison Foerster

Morrison Foerster stands out for its expertise in the tech, telecoms, and life sciences sectors, advising major international names in these industries and others on merger clearances, including FTC Second Request investigations and investigations in Europe and Asia, with notable ongoing involvements in the semiconductor space. Major clients for the firm include Target, UPS, and newly-acquired clients Salesforce and Showingtime, who co-head Alexander Okuliar and Megan Gerking represented in its $500m acquisition by Zillow Group. Co-chair Lisa Phelan remains highly active in contentious investigations, as does Jeff Jaeckel, also a key name for cross-border merger approval processes. Former DOJ Antitrust Division official David Shaw is noted for his Big Tech expertise, and regularly handles litigation arising from contested and proposed mergers. All lawyers mentioned are in Washington DC.

Practice head(s):

Alexander Okuliar; Lisa Phelan

Other key lawyers:

Megan Gerking; David Shaw; Jeff Jaeckel

Key clients




Tencent Holdings Limited



Unity Software

Axalta Coating Systems

Matsuo Electric Co, Ltd.

McGrath RentCorp


ON Semiconductor

DSP Group, Inc.


SoftBank Group Corp. & Arm Limited

Jean-Paul Van Avermaet, Former CEO of G4S

Nexstar Media Group, Inc


Tiz Inc. d/b/a Provi

Restoration Hardware


Work highlights

  • Represented, Inc in its $500 million acquisition by Zillow Group, Inc.
  • Advised SoftBank Group and Arm Limited on complex antitrust and national security issues in the EU, United States, and Asia, arising from NVIDIA’s proposed acquisition of Arm from SoftBank for USD$65 billion.
  • Represented Southwest Gas in connection with its proposed acquisition of Quester Pipeline for approximately $2 billion and Carl Icahn’s unsolicited tender offer to acquire 100% of the outstanding shares of Southwest Gas for approximately $4.2 billion.

Shearman & Sterling LLP

Offering strength in complex and contentious merger proceedings on both sides of the Atlantic, the team at Shearman & Sterling LLP  works with major US and global clients, often on a hired-gun basis, to secure approvals for deals in a diverse range of sectors, including aerospace and defense, tech, media, and financial services. The practice has deep agency experience, including former senior DOJ and FTC officials, allowing it to advise clients on agency strategy throughout Second Request proceedings and other high-stakes merger investigations and litigation. The firm handled two standout mandates for JetBlue in 2022, representing the client against the DOJ’s challenge to its alliance with American Airlines, as well as advising on its $3.8bn takeover bid for Spirit Airlines, both significant cases for key senior lawyer Jessica Delbaum . A former Chief of Staff at the Antitrust Division, global antitrust head David Higbee is noted for his expertise in regulated industry deals, representing clients before US and international antitrust agencies, while Ben Gris is another active member of the team, previously Assistant Director of the FTC’s Bureau of Competition and focusing on merger-related investigations and litigation. All lawyers mentioned are in Washington DC. Ryan Shores has left the firm.

Practice head(s):

David Higbee; Jessica Delbaum; Ben Gris


‘The Team at Shearman is available and very informed on all antitrust, foreign investment and merger control issues across multiple jurisdictions. Their advice is practical and collaborative.’

Key clients


Paramount Global



Booz Allen Hamilton

PSA International

Fairfax Financial

Glatfelter Corporation

Dover Corporation

Sun Pharmaceuticals

Work highlights

  • Represented Booz Allen Hamilton in the U.S. Department of Justice’s attempt to block its $440 million acquisition of EverWatch.
  • Advising JetBlue Airways Corporation in connection with its strategic Northeast Alliance with American Airlines, including on a lawsuit by the DOJ and six states as well as the District of Columbia alleging that the Alliance violates Section 1 of the Sherman Act.
  • Representing Paramount Global and Simon & Schuster in the litigation brought by the DOJ to block the pending sale of Simon & Schuster to German media giant Bertelsmann.

Vinson & Elkins LLP

Vinson & Elkins LLP offers a broad nationwide antitrust practice with a strong presence across Washington DC, Texas, and California, working with clients in highly scrutinized sectors such as energy, tech, chemicals, and pharma on merger clearances, combining prolific HSR filing work with a successful record in antitrust litigation relating to contested mergers. The team focuses on cross-border mergers, encompassing multijurisdictional filings and approval proceedings, alongside investigations by international regulators, best evidenced by co-head Darren Tucker’s representation of Google in its $2.1bn acquisition of Fitbit, which required European, Canadian, and Latin American merger approvals and was subject to international investigation. Co-head Hill Wellford is also noted for his specialism in antitrust investigations by the FTC and DOJ, including several high-profile merger cases. Vastly experienced antitrust litigator Alden Atkins  has a strong focus on the energy and infrastructure sectors, while Zachary Terwilliger, formerly United States Attorney for the Eastern District of Virginia, is also a key team member, focusing on contentious merger cases and trials. All lawyers mentioned are in Washington DC.

Practice head(s):

Darren Tucker; Hill Wellford

Other key lawyers:

Alden Atkins; Zachary Terwilliger

Key clients

Google LLC


Wanhua Chemical (America) Co., Ltd.

AirTran Airways

Targa Resources Corp.


Southwest Airlines, Inc.

Calumet Specialty Products

Maxell, Ltd. And Maxell Corporation of America


Switchback II Corporation

Enable Midstream Partners, LP

Group 1 Automotive, Inc.

ioneer Lrd.

The Sinclair Companies

Liberty Oilfield Services Inc.


Direct Energy

Noble Energy, Inc.

Plains All American

Chevron Phillips Chemical Co.

Vida Capital, Inc.

National Association of Chain Drug Stores

Oregon Dental Service d/b/a Delta Dental of Oregon

Delta Dental Plan of Wyoming d/b/a Delta Dental of Wyoming

United States Steel Corporation

Lukoil Pan Americas LLC

Foster Poultry Farms

HeartBrand Holdings, Inc.


Huntsman International

Phadia US Inc.

Magellan Crude Oil Pipeline Company, L.P.

AK Steel Corporation, et. Al – railroad MDL

Work highlights

Wachtell, Lipton, Rosen & Katz

Wachtell, Lipton, Rosen & Katz is active on high-stakes merger clearances in the US and globally, advising the firm’s clients, which include major names in financial services, pharma, and energy, on FTC and DOJ filings, investigations, and litigation, as well as co-ordinating multi-jurisdictional merger filings and approvals. Offering agency experience and a strong record in contentious merger clearances, he team handles complex, high-value transactions, including CAA’s acquisition of ICM Partners, a major win for practice head Ilene Gotts, while Nelson Fitts  successfully represented Sanderson Farms in the DOJ’s investigation of its $4.5bn acquisition by Cargill and Continental Grain. Christina Ma is active in the financial services space, and is noted for her risk analysis capabilities, advising clients on potential agency action ahead of proposed transactions. All lawyers mentioned are in New York.

Practice head(s):

Ilene Gotts

Other key lawyers:

Nelson Fitts; Christine Ma

Key clients

Sanderson Farms



Black Knight



Siris Capital




Work highlights

  • Represented Sanderson Farms in the DOJ’s investigation of its acquisition by Cargill and Continental Grain, which combined the third (Sanderson) and seventh (Wayne Farms) largest chicken processing firms in the U.S.
  • Represented S&P Global in its $44 billion acquisition of IHS Markit, which combined two of the largest data providers to the financial and commodities industries. The deal was subject to a year-long investigation by the U.S. Department of Justice, the European Commission and the UK’s Competition and Markets Authority, as well as other foreign regulators.
  • Represented Hilrom in its $12.4 billion all-cash acquisition by Baxter International, bringing together two leading medical technology companies to broaden access to care in the hospital, home and alternate site settings.


The team at Akin has long-standing experience in merger litigation, representing clients in a number of high-stakes contested mergers before the DOJ and FTC, as well as having a successful record in shepherding strategic M&A through the clearance process. The firm has notable strength in the retail and manufacturing industries, and regularly handles complex processes such as divestment orders and issues relating to intellectual property in mergers. Corey Roush leads the team, having litigated against both the DOJ and FTC, with Gorav Jindal also a highly experienced antitrust litigator. Former FTC official Haidee Schwartz is an expert in domestic and international merger review processes, and offers experience on both sides of merger investigations, while counsel Brian Rafkin specializes in litigated merger challenges. All lawyers are based in Washington DC.

Practice head(s):

Corey Roush

Other key lawyers:

Haidee Schwartz; Gorav Jindal; Brian Rafkin; Matthew Schmitten

Key clients

Seven & I Holdings Co., Ltd. (7-Eleven, Inc.)

Services Group, Inc.

U.S. Concrete, Inc.

Enterprise Product Partners

Work highlights

  • Advised 7-Eleven in its blockbuster $21 billion acquisition of Speedway.
  • Advising Services Group in its $240 million sale to Superior Plus Propane, a subsidiary of Superior Plus Corp.
  • Advised U.S. Concrete in the company’s $1.3 billion sale to Vulcan Materials.

Allen & Overy LLP

Allen & Overy LLP stands out for its work on complex cross-border merger clearances, working with a global client base in industries such as energy, tech, and financial services on merger filings, investigations, and regulatory challenges before the DOJ, FTC, and European antitrust agencies, regularly collaborating with its London and Brussels offices on multijurisdictional mandates. The team also has notable expertise in the private equity space, advising funds such as Advent international on complex portfolio company mergers and disposals subject to antitrust scrutiny. New York’s Elaine Johnston, a specialist in cross-border merger strategy, leads the team alongside tech-focused Noah Brumfield in Washington DC, who represented GlobalWafers in its high-profile attempted $5.4 billion takeover of rival Siltronic. Senior associate and ‘fantastic legal partnerPuja Patel , also in New York, is a key member of the team, playing important roles in a number of complex mergers and Second Request investigations.

Practice head(s):

Elaine Johnston; Noah Brumfield

Other key lawyers:

Puja Patel


‘A solid global practice that is able to advise on complex global transactions.’

‘Puja Patel is a fantastic legal partner as an associate. She understands the issues and tries to come up with workable solutions, but is also direct when necessary.’

Key clients

Advent International

GlobalWafers Co., Ltd.

EQT Partners AB and various EQT funds

Intercontinental Exchange (ICE)

Animal Logic

Mubadala Investment Company PJSC

WillScot Mobile Mini



A.P. Møller – Mærsk A/S

Koninklijke DSM N.V.


LeasePlan N.V.

Element Materials Technology

Sweet Harvest Foods Holdings, LLC

Savvy Gaming Group

Bridgepoint and its portfolio company, PharmaZell

Work highlights

  • Represented Advent International in relation to the establishment of a joint venture with LANXESS AG, which will acquire DSM’s Engineering Materials business and hold LANXESS’s High Performance Materials business post-transaction.
  • Represented GlobalWafers Co., Ltd. on its attempted $4.89 billion acquisition of Siltronic AG.
  • Represented EQT Partners AB in connection with its significant minority investment in Special New Fruit Licensing.

Axinn Veltrop & Harkrider

Axinn Veltrop & Harkrider is a specialist antitrust firm with a successful record in high-value, strategic merger clearances, focusing on complex and business-critical transactions for major US businesses facing regulatory scrutiny by US and international agencies on a hired gun basis. The firm combines its active merger work with contentious and litigation expertise, representing major corporations in fields such as manufacturing, pharma, and tech against government actions arising from merger activity. The firm is headed up by Michael Keeley, who is prolific in the merger space, representing major repeat clients such as Thermo Fisher and Tyson Foods, alongside New York-based John Harkrider, a vastly experienced antitrust counsel who successfully advised VMWare on its $69bn pending acquisition by Broadcom, and Lisl Dunlop. Bradley Justus is also a key team member, regularly handling FTC, DOJ, and global merger reviews in diverse jurisdictions and industries, with former senior DOJ official Leslie Overton noted for her combination of contentious and non-contentious merger work. James Attridge joined the team in September 2022, having previously served as Chief of Staff at the Antitrust Division. Lawyers are in Washington DC unless otherwise stated.

Practice head(s):

John Harkrider; Michael Keeley

Other key lawyers:

Bradley Justus; Lisl Dunlop; James Attridge; Leslie Overton

Key clients


Take-Two Interactive Software

McKesson Corporation

Thermo Fisher Scientific Inc.

Stanley Black & Decker Inc.

Dell Technologies

Ricoh Company Ltd.

Valora Holding AG

Work highlights

  • Representing VMware, Inc in its USD $69 billion pending acquisition by Broadcom Inc.
  • Represented Take-Two Interactive Software, Inc on antitrust matters in its USD $12.7 billion acquisition of Zynga.
  • Represented Thermo Fisher Scientific Inc in its approximately USD $1.85 billion acquisition of PeproTech, Inc.

Clifford Chance

Clifford Chance combines institutional relationships with major businesses and private equity funds as merger counsel with high-profile hired gun instructions from key names in fields such as healthcare, education, and consumer goods, handling cross-border strategic merger clearances as well as DOJ and FTC investigations and related litigation, with standout capabilities in acting for third parties objecting to proposed mergers and advising on multijurisdictional approvals for transactions in healthcare and life sciences. In a major development for the team, Leigh Oliver arrived from Hogan Lovells US LLP in March 2022, and promptly successfully represented UnitedHealth Group in its acquisition of Change Healthcare, a $13bn deal that faced significant scrutiny from the Antitrust Division and state attorneys general, while HSR specialist Brian Concklin was promoted to partner in May 2022. The team is led by former acting Assistant Attorney General Sharis Pozen, who has also held senior antitrust positions at the FTC and in-house, and specialises in complex merger litigation, and Timothy Cornell, a key name for multijurisdictional clearances processes and investigations. Former DOJ official Peter Mucchetti is also a key team member, with expertise in healthcare and consumer goods mandates. All lawyers mentioned are in Washington DC.

Practice head(s):

Timothy Cornell; Sharis Pozen

Other key lawyers:

Brian Concklin; Leigh Oliver; Peter Muchetti

Key clients

General Electric

Philip Morris International

Stephen King

UnitedHealth Group


CVC Capital Partners

Partners Group

BMO Capital Markets Corp. (Bank of Montreal)

ICBC Standard Bank Plc.

Informa PLC

Royal DSM


State University of New York

Hitachi Rail (“Hitachi”)

Epic Games

Orthofix Medical Inc.





Work highlights

  • Advised General Electric with regards to AerCap Holdings N.V.’s (AerCap) acquisition of GE Capital Aviation Services business (GECAS).
  • Advised Philip Morris International (“PMI”) on its cash tender offer of Swedish Match AB.
  • Advised Philip Morris International on responding to third-party document and deposition subpoenas issued by the U.S. Federal Trade Commission.

Hughes Hubbard & Reed LLP

Hughes Hubbard & Reed LLP handles a large number of DOJ and FTC clearance processes for deals in a wide range of industries, representing major clients in telecoms, private equity, and pharma, among others. The Washington DC-based team, led by former Deputy Assistant Attorney General William J. Kolasky , is also able to handle contentious regulatory investigations and enforcement actions relating to mergers, as well as approvals by merger authorities in global jurisdictions. Robert B. Bell  is highly experienced in merger clearances, and also offers deep knowledge of vertical distribution arrangements relating to transactions, while Philip Giordano is a former DOJ antitrust enforcer and focuses on the financial services sector. Associate Kristin Millay has a strong record in HSR pre-merger notifications and DOJ merger investigations.

Practice head(s):

William J. Kolasky

Other key lawyers:

Philip Giordano; Kristin Millay; Robert B. Bell


‘William Kolasky is outstanding. Smart, responsive and very creative.’


Key clients

Sinclair Broadcast Group Inc.

Avfuel Corporation

Egan-Jones Ratings Co.

Isos Acquisition Corp


ANI Pharmaceuticals

Greenbriar Equity Group

CF Acquisition Corp VI






Kensington Capital Acquisition Corp II, IV

ION Investment Group

Work highlights

  • Advising CF Acquisition Corp. VI, a SPAC sponsored by Cantor Fitzgerald, in a pending transaction with Rumble Inc. that will take the Canadian neutral video platform public.
  • Represented global information technology company Wipro in its acquisition of Edgile, a cybersecurity consulting provider for $230 million.
  • Advised global animal health company Zoetis on strategic investments in two animal health focused venture funds, Parallel F&A Ventures II C.V.


Milbank bolstered its team with the arrival of ‘outstanding lawyerAdam Di Vincenzo from Gibson Dunn in June 2022, adding significant experience in the energy and infrastructure antitrust space and establishing the firm’s presence in Washington DC, while senior counsel Daniel Rosenthal joined in August 2022 from White & Case LLP, specializing in government investigations. The firm continues to be active on domestic and cross-border deals within energy and infrastructure as well as private equity, with standout clients including the Carlyle Group, and is able to handle HSR filings alongside agency investigations and challenges, with experience in litigation before state and federal courts. The ‘smart and drivenFiona Schaeffer, a highly experienced advisor on bet-the-company mergers in key sectors such as healthcare, financial services, and media, leads the team. Lawyers are based in New York unless otherwise stated.

Practice head(s):

Fiona Schaeffer

Other key lawyers:

Adam Di Vincenzo; Daniel Rosenthal; Andrew Wellin


‘I have worked with Fiona Schaeffer for many years, mostly in the leadership of the ABA Antitrust Law Section. Based on her dedication, terrific work, and collegiality, Fiona will become Chair of the Section, a very prestigious position, in August 2023. I am fully confident that Fiona provides top quality legal counsel and client service in every aspect of antitrust and competition law.’

‘Adam Di Vincenzo is an outstanding lawyer. Bright, organized, experienced, calm, persuasive, and strategic. He does a great job building a strong working relationship with Agency staff. It is also fun to work with Adam because he is a great person. I couldn’t recommend him more highly.’

Fiona Schaeffer is fantastic! She is smart and driven. She keeps pushing and pushing in an Agency setting and her persistence wears down staff and leads to great outcomes for her clients. Highly recommended.

‘Andrew Wellin is sharp and exceptionally hard-working. Recommended.’

Key clients

Sartorius Stedium Biotech S.A.

Veritas Capital

Abra Group Limited

Houghton Mifflin Harcourt

The Carlyle Group/Carlyle Aviation Partners

Molina Healthcare, Inc.

Patricia Industries

Cenovus Energy, Inc.


Work highlights

  • Advising SLB in connection with a planned joint venture with a direct competitor.
  • Advising Veritas Capital on HSR filings and merger control analyses, as well as leading the substantive antitrust defense of all deals.
  • Advised on the ~$1.7 billion creation of Abra, a leading air transportation group operating across Latin America.

O'Melveny & Myers LLP

O'Melveny & Myers LLP continues to handle major merger cases before the DOJ and FTC, notably representing Penguin Random House in the high-profile DOJ merger challenge of Penguin’s proposed $2.18bn acquisition of Simon & Schuster from ViacomCBS, a case which attracted significant national attention, demonstrating the firm’s record as an antitrust counsel in complex transactions and government challenges. Elsewhere, the firm advises on domestic and cross-border approvals in sectors such as semiconductors, agriculture, and aerospace, acting for buyers as well as third parties challenging deals. The Washington DC-based team is led by Courtney Dyer, who advises on merger investigations and Clayton Act issues relating to joint ventures, as well as related litigation, and experienced trial lawyer Katrina Robson, a go-to for merger litigation. Julia Schiller, formerly of the DOJ Antitrust Division, played a key role in the Penguin Random House proceedings.

Practice head(s):

Courtney Dyer; Katrina Robson

Other key lawyers:

Julia Schiller

Key clients

Alaska Airlines

American Airlines

Asiana Airlines

AT&T, Inc.

Babcock & Wilcox

Charles Schwab


DL Chemical

Home Depot

Penguin Random House LLC

Qatar Airways

Quest Diagnostics

Rea Magnet Wire Co.

Semtech Corporation

Sureprep, LLC

Tractor Supply Co

TTM Technologies

Work highlights

  • Defending Penguin Random House in the DOJ Antitrust Division’s challenge of its proposed $2.175 billion acquisition of Simon & Schuster.
  • Represented Tractor Supply Company in the FTC’s Second Request investigation and conditional clearance of the $297 million acquisition of Orscheln Farm and Home.
  • Advising Asiana Airlines on its proposed acquisition by Korean Air Lines Co., Ltd., which is under review in several jurisdictions including China, Europe, the U.K., and the United States.

Orrick, Herrington & Sutcliffe LLP

Orrick, Herrington & Sutcliffe LLP specializes in complex merger control cases for tech clients including software and robotics companies, advising on FTC and DOJ oversight of innovative strategic acquisitions, as well as advising clients on other regulated industries such as energy and pharma on merger filings, investigations, and regulatory actions. Eileen Cole offers deep experience of technology regulation, while Craig Falls has a successful record in DOJ, FTC, and state attorneys general merger processes. Amy Ray now leads the team and is also active in the tech space, as well as picking up work for new clients including Superior Plus US Holding. The team was bolstered in November 2022 by the arrival of antitrust investigations specialist Anna Aryankalayil from the FTC. All lawyers are based in Washington DC. Jay Jurata left the firm in February 2023.

Practice head(s):

Amy Ray

Other key lawyers:

Craig Falls; Eileen Cole; Anna Aryankalayil

Key clients

Microsoft Corporation

Novitium Pharma LLC

Superior Plus US Holdings





Work highlights

  • Advised Novitium Pharma, a pharmaceutical company with development, manufacturing, and commercialization capabilities, in its $163.5 million acquisition by ANI Pharmaceuticals.
  • Advised Superior Plus on its $240 million acquisition of retail competitor Kamps Propane and wholesale competitors Kiva Energy, among other related entities, operating in Northern California.
  • Advised Ipsen SA, a French specialty and generic drug manufacturing company, in its $247 million acquisition of Epizyme.

Paul Hastings LLP

Paul Hastings LLP advises a wide range of clients on contested strategic mergers, with a team offering extensive in-house and agency expertise across contentious and non-contentious merger reviews, investigations, and associated litigation. The firm has a notable focus on growth industries including tech, life sciences, energy, and cannabis, acting for major cannabis players such as Cresco Labs and Canopy Growth, as well as regularly working with third parties objecting to proposed mergers. Also of note is the firm’s global platform, with the US team regularly collaborating with European and Asian offices on complex multijurisdictional approval processes and regulatory investigations. Michael Wise is the key name for merger control work, advising prolifically on merger approval processes, including the standout representation of Symphony Technology Group in the acquisitions of FireEye from McAfee, while practice head Gary Zanfagna has deep in-house and private practice experience in merger review cases, encompassing acquisitions, divestments, and joint ventures, particularly in the life sciences space. Former Principal Deputy Assistant Attorney General Michael Murray is also a key name, having coordinated merger proceedings and trials as both a regulator and an attorney. All lawyers mentioned are in Washington DC.

Practice head(s):

Gary Zanfagna

Other key lawyers:

Michael Murray; Michael Wise; Mary Bowser


‘Gary Zanfagna is practical and a clear communicator. Strategic advice that aligns with business realities.’

‘Gary Zanfagna is a stand-out contributor on the team. He is able to distill complex materials in a way that makes sense within business objectives.’

‘The Paul Hastings team did a great job. They had a lot of new ideas in managing HSR filings which I had never heard of before. I thought they did a great job of interacting with the DOJ.’

Key clients

SD Biosensor


SLJ Partners

HYBE (formerly Big Hit Entertainment)

Symphony Technology Group

Barclays Bank PLC, Barclays Capital Inc., Barclays Services Ltd., Barclays Capital Securities Ltd.

RBC Capital Markets, LLC (“RBC”)

Align Technology, Inc.

Cresco Labs

Canopy Growth

Work highlights

  • Representing SJL Partners and SD Biosensor in the antitrust reviews of their proposed joint venture to acquire Meridian Biosciences.
  • Represented non-party witnesses, as well as five additional non-parties, in the US DOJ suit to enjoin book publisher Penguin Random House’s proposed acquisition of Simon & Schuster.
  • Representing Symphony Technology Group in the acquisitions of McAfee’s enterprise business and internet security firm FireEye. Both companies are active in providing cybersecurity for large enterprises.

Ropes & Gray LLP

Ropes & Gray LLP offers broad expertise across DOJ and FTC merger processes, advising a broad range of corporate and private equity clients on  HSR filings through to investigations and regulatory actions, as well as coordinating global merger approvals in concert with its international offices. The firm is particularly strong in the life sciences space, advising strategic purchasers and investors on contested transactions facing significant regulatory scrutiny, such as Medtronic’s $1.1bn acquisition of Intersect ENT, which succeeded following a FTC Second Request in a notable victory for the highly experienced Michael McFalls  and former FTC Mergers I head Jonathan Klarfeld . Additionally, the firm is active in handling merger filings and strategy for private equity clients such as Bain Capital, with the prolific Deirdre Johnson in Boston specializing in HSR work. Mark Popofsky  oversees the team, which also includes Samer Musallam, who focuses on merger-related investigations in a range of regulated sectors, including medical devices, telecoms, and semiconductors. Jacqueline Grise joined the firm in April 2024 from Cooley LLP. All attorneys are in Washington DC unless otherwise stated.

Practice head(s):

Mark Popofsky

Other key lawyers:

Samer Musallam; Deirdre Johnson; Jonathan Klarfeld; Michael McFalls

Key clients

Google Inc.

Signify Health


Harvest Partners

New Mountain Capital


Gingko Bioworks


Bain Capital

Thomas H. Lee Partners


TriArtisan Capital Advisors

Fidelity Investment Management

Work highlights

  • Advised Pfizer Inc. on the merger control aspects relating to its $5.4 billion acquisition of Global Blood Therapeutics, Inc.
  • Advised Medtronic Inc. in its $1.1 billion acquisition of Intersect ENT, a well-known publicly traded healthcare equipment company.
  • Represented TPG Capital in its acquisition of ClaimsXten, Change Healthcare’s claims payment and editing business, from UnitedHealth for $2.2 billion.

Sheppard, Mullin, Richter & Hampton LLP

Sheppard, Mullin, Richter & Hampton LLP has a prolific record in HSR filings and merger review processes, advising a wide range of businesses and private equity investors on approvals for deals in diverse sectors, with a particularly strong focus on the healthcare space. The team also offers significant agency review and contentious expertise through John Carroll, a former FTC official who represents clients before the DOJ Antitrust Division, FTC, and international and state antitrust enforcement authorities. Bevin Newman specializes in healthcare antitrust matters, advising on merger control cases relating to acquisitions, collaboration agreements, and joint ventures across the sector, while Century City-based David Garcia is a key name for contested mergers, regularly representing hospital and physician groups. Leo Caseria specializes in HSR filings, while special counsel Malika Levarlet focuses on approvals for cross-border transactions. Lawyers are in Washington DC unless otherwise stated.

Other key lawyers:

John Carroll; Bevin Newman; David Garcia; Leo Caseria; Malika Levarlet

Key clients

U.S. Brick




Quixote Studios

Work highlights

  • Representing VillageMD in its agreement to acquire Summit Health-CityMD.
  • Representing U.S. Brick, a leading manufacturer of bricks and other building materials in the United States, as the purchaser of certain assets being divested by Meridian and General Shale, pursuant to a Department of Justice, Antitrust Division Consent Decree.
  • Represented BitGo in antitrust aspects of its $1.2 billion acquisition by Galaxy Digital Holdings Ltd.

Willkie Farr & Gallagher LLP

Willkie Farr & Gallagher LLP remains highly active across domestic and cross-border merger proceedings, combining a strong record in DOJ and FTC approval processes with capabilities in international reviews and investigations, with the team regularly collaborating with its European and UK offices on multijurisdictional mergers. The firm also enjoys standout international contentious expertise, again collaborating with its international offices on merger litigation, and is able to handle complex cases in diverse and highly-scrutinized industries such as financial services, tech, and pharma. William Rooney co-leads the team, and is a vastly experienced antitrust counsel, handling contentious and non-contentious merger reviews and related litigation, notably advising Trussway on all antitrust aspects of the sale of the company to BFS Group LLC, while co-head Jeffrey Korn is noted for his focus on matters and regulatory investigations before US and European antitrust enforcement agencies. Counsel Agathe Richard also has notable experience of US and European merger approval processes, and played a key role on Kaseya’s $6.2bn acquisition of Datto. All lawyers mentioned are in New York.

Practice head(s):

William Rooney; Jeffrey Korn

Other key lawyers:

Agathe Richard; Matthew Freimuth; Wesley Powell


‘I was very impressed with Willkie’s merger control practices speed and responsiveness as well as their ability to quickly coordinate across multiple jusrisdictions and with a number of counterparties. Their advice was practical, commercial and efficient.’

Key clients

Akorn, Inc.

Alleghany Corporation

Arkema Group

Choice Hotels International, Inc.

Cornerstone Healthcare Group

Forum of Firms

Franklin Templeton

Gallant Capital Partners

Highland Capital

Kaseya Limited, a portfolio company of Insight Partners

Lakeside Book Company, a portfolio company of Atlas Holdings, LLC

Lagardère Group

Mueller Industries, Inc.


Teva Pharmaceutical Industries Ltd.

The CapStreet Group

Trussway Manufacturing

Third Point

Work highlights

  • Advised Alleghany Corporation on all antitrust aspects related to its $11.6 billion acquisition by Berkshire Hathaway.
  • Advised Trussway on all antitrust aspects of the sale of the company to BFS Group LLC.
  • Advised Kaseya on all antitrust aspects of its $6.2 billion acquisition of Datto.


WilmerHale combines an active HSR practice with strong capabilities in contentious merger review proceedings, handling approvals for transactions in highly-scrutinised industries including defense, healthcare, and telecoms. The team is able to leverage strong litigation and enforcement expertise, as well as multijurisdictional capabilities, representing international and US-based clients in multi-agency reviews and challenges. The team is overseen by Thomas Mueller, who has strong litigation experience and has practiced in the US and Brussels, while Leon Greenfield is noted for his leading role in high-value deals for major clients such as Danaher. Former FTC official Dominic Vote is also heavily focused on merger control mandates. All lawyers mentioned are in Washington DC.

Practice head(s):

Thomas Mueller

Other key lawyers:

Leon Greenfield; Dominic Vote

Key clients


Charles Schwab


Baker Hughes

Work highlights

Alston & Bird LLP

Alston & Bird LLP has notable capabilities in multijurisdictional merger clearances, regularly advising clients in industries such as telecoms, private equity, and manufacturing on transactions requiring European and UK approvals such as the Ali Group’s $4.5bn acquisition of Welbilt, alongside representing clients in FTC and DOJ merger processes, investigations, and antitrust litigation relating to proposed deals. Washington DC’s practice co-head Adam Biegel is an experienced antitrust counsel who handles all elements of merger clearance; co-head Matthew Kent in Atlanta takes the lead on HSR filings for mergers and joint ventures, as well as substantive merger reviews. Also in Washington DC, John Snyder is noted for his regulatory and enforcement expertise.

Practice head(s):

Adam Biegel; Matthew Kent; Teresa Bonder

Other key lawyers:

John Snyder

Key clients

Ali Group

Work highlights

  • Representing the Ali Group in conjunction with its $4.5 billion acquisition of Welbilt Inc.

Baker McKenzie LLP

Baker McKenzie LLP handles merger review processes for an international client base, advising major names such as Bayer and Nielsen on strategic acquisitions, with expertise encompassing US and global merger approvals, foreign investment control, and regulatory issues across relevant jurisdictions. The firm is noted for its integration with its global platform, working regularly with offices in Europe and Asia on cross-border matters, and handles transactions across the telecoms, life sciences, manufacturing, and consumer goods sectors. Mark Hamer and Creighton Macy lead the team, both former DOJ officials with experience in co-ordinating contentious and non-contentious merger investigations, while Brian Burke  is a go-to for clients in a diverse range of industries in merger cases before the DOJ and FTC. All lawyers mentioned are in Washington DC.

Practice head(s):

Mark Hamer; Creighton Macy

Other key lawyers:

Brian Burke

Key clients


Quest Diagnostics

EDR LightBox

NHK Spring

Bayer AG




Benefytt Technologies

Sika AG


Helen of Troy


Work highlights

  • Advised Nielsen Holdings plc on its $16bn divestment of the Nielsen Holdings business to Elliott Investment Management and Brookfield Business Partners.

Cahill Gordon & Reindel LLP

Cahill Gordon & Reindel LLP in New York combines a strong specialism in financial services antitrust work, encompassing mergers and investment analysis advice, with a growing number of major corporate merger mandates, representing global clients in diverse industries such as Lufthansa, 1-800 Flowers, and American Express. The team is able to advise on FTC and DOJ approvals for domestic transactions, as well as handling cross-border merger control matters involving international regulatory authorities, including ICON’s $12bn acquisition of Watford. Counsel Lauren Rackow works regularly with banking and financial services clients, as well as playing a key role in antitrust approvals for major clients such as Shutterstock. Elai Katz left the firm in August 2023.

Practice head(s):

Herbert Washer; David Januszewski

Other key lawyers:

Lauren Rackow


‘Excellent firm and strong reputation for antitrust – our firm has partnered with Cahill on two mandates this calendar year – both of which were transactional / merger control related.’

‘Elai Katz – he is a highly effective and experienced anti-trust lawyer and is very active in the ABA (hosting events at the Spring Meeting in Washington DC).’

Lauren Rackow is excellent – thorough and diligent and worked very effectively.

Key clients

Credit Suisse

American Express


Arch Capital Group


ICON plc


Deutsche Bank

JP Morgan

S&P Global

Work highlights

  • Representated of ICON plc in its $12 billion acquisition of PRA Health Sciences, forming one of the world’s leading contract research organizations.
  • Representated of Shutterstock, Inc. in its acquisitions of Pond5 and Splash News, providing customers with unparalleled access to one of the largest collections of editorial and commercial video content in the world.
  • Advising financing sources in dozens of the most complex, multi-billion dollar global transactions.

Cooley LLP

Standing out for its work in the tech and life sciences spaces, the team at Cooley LLP works with tech and pharma companies on US and international merger clearances, handling strategic and growth acquisitions for market disruptors as well as established global players, as well as representing clients facing regulatory oversight as a result of merger activity, encompassing investigations as well as merger litigation both in the US and against global enforcement bodies. Former FTC Bureau of Competition official Howard Morse handles merger investigations by FTC, DOJ, and state attorneys general. Megan Browdie is particularly strong in the healthcare and life sciences space, while Kathy O’Neill joined from the DOJ’s top civil antitrust role in September 2022, contributing significant expertise in merger investigations across industries. All lawyers mentioned are in Washington DC. Jacqueline Grise left the firm in April 2024.

Other key lawyers:

Howard Morse; Megan Browdie; Kathy O’Neill

Key clients

Intersect ENT

1Life dba One Medical

Arena Pharmaceuticals

Meredith Corporation

Horizon Therapeutics



ZOLL Medical


Jazz Pharmaceuticals

Work highlights

  • Advised Intersect ENT on the global antitrust aspects of its sale to medical technology company Medtronic in an all-cash transaction valued at $1.1 billion.
  • Represented ViaCyte in its sale to Vertex for $320 million.
  • Representing One Medical in its $3.9 billion sale to Amazon.

Fenwick & West LLP

Fenwick & West LLP combines a strong specialism in the tech and life sciences sectors with strong agency approvals expertise, expanding its share of high-profile clients in a wide range of industries thanks to a developing presence in Washington DC. The team acts for names such as Clif Bar, Figma, and Acadia Healthcare Company, handling DOJ and FTC approvals for deals, as well as advising on transactions requiring multijurisdictional approvals, and handling innovative take-private and PIPE structures from an antitrust perspective. Thomas Ensign co-heads the team from Washington DC, leading on major deals such as Clif Bar’s acquisition by Mondelez, with Silicon Valley-based fellow co-head Mark Ostrau  specializing in tech and cybersecurity transactions. Also in DC, Steve Albertson is a highly experienced merger counsel, handling business-critical deals and investment rounds, while associate Elizabeth Suarez stands out for her work advising clients on US and international merger control processes, as well as government investigations.

Practice head(s):

Thomas Ensign; Mark Ostrau

Other key lawyers:

Steve Albertson; Elizabeth Suarez


‘Fenwick has handled a high profile merger control issue for our company, and they’ve done a commendable job.’

‘Tom Ensign comes highly recommended. He is a very good lawyer and remains available and focused on delivering excellent client service.’

Key clients










Faire Wholesale


Acadia Healthcare Company, Inc.

Sanderling Renal Services


Work highlights

  • Representing Figma, a leading web-first collaborative design platform, in its pending US$20 billion acquisition by Adobe.
  • Represented Clif Bar & Company in its acquisition by Mondelēz International for US$2.9 billion.
  • Represented Vocera Communications, Inc. in its definitive agreement to be acquired by Stryker.

King & Spalding LLP

The Washington DC-based team at King & Spalding LLP handles complex, high-value merger review processes alongside regulatory investigations and litigation arising from contested mergers, working with major names in tech, chemicals, and education, including notable new transactional mandates for Rice University and Cox. The practice offers US-wide expertise, cross-border capabilities, and significant agency experience, with practice co-head Norm Armstrong previously serving as Deputy Director and Deputy Assistant of the FTC’s Bureau of Competition, while co-head Jeff Spigel has a successful record in acting before the DOJ and FTC in strategic merger filings and investigations, as well as regularly working on multijurisdictional transactions requiring global antitrust approvals.

Practice head(s):

Norm Armstrong; Jeff Spigel

Key clients


ACON Investments


BASF Corporation

Cornell University


Deutsche Bank



Evangelical Community Hospital

Genuine Parts Company



H.I.G. Capital

Hunter Douglas

J.R. Simplot Company

ManTech International Corporation

Ochsner Health System

Peloton Interactive, Inc.

Piedmont Healthcare

Queen’s Health System

Quikrete Holdings, Inc.

Rice University

The Home Depot

Trafigura Trading LLC

United Parcel Service

Viserion Grain, LLC

Westrock Company

Work highlights

  • Representing EVO Payments, Inc. in a DOJ Antitrust Division investigation of EVO’s proposed acquisition by Global Payments valued at US$4 billion.
  • Represented ManTech International Corporation in its sale to funds managed by global investment firm The Carlyle Group, in an all-cash transaction with a total enterprise value of approximately US$4.2 billion.
  • Represented Quikrete Holdings, Inc. in its acquisition of Forterra Inc. The parties received a Second Request from the DOJ and negotiated a settlement with the DOJ that allowed the parties to close on their transaction.