Sidley Austin LLP > Washington DC, United States > Firm Profile

Sidley Austin LLP
United States

M&A/corporate and commercial > Shareholder activism Tier 1

Sidley Austin LLP has a strong track record and market reputation in shareholder activism, both domestically and internationally, and is ‘full of skilled attorneys‘ who work on high profile activism matters for household name clients such as The New York Times Company. The team includes two specialist activism and takeover defense practitioners in Derek Zaba, who splits his time between Palo Alto and New York, and Kai Liekefett in New York, with the pair referred to as ‘great lawyers who have a very good practice representing public companies defending against activist investors’, and are well supported by Jessica Wood in New York, who has represented a wide range of public companies against shareholder activism.  Leonard Wood in Houston was promoted to partner in January 2023, and is a key team member experienced in takeover defense, with specialist expertise in investor pressure connected to ESG issues.

Practice head(s):

Kai Liekefett; Derek Zaba

Other key lawyers:


‘Full of skilled attorneys.’

‘Derek Zaba and Kai Liekefett are great lawyers who have a very good practice representing public companies defending against activist investors.’

Deep experience and leadership in area of activism defense. A practice singularly focused in this area and with partners who are respected in the industry.

Key clients

The New York Times

Hasbro, Inc.

Box, Inc.

Alkermes, Inc.

Zendesk, Inc.

Momentive Global Inc.

SpartanNash Company

US Foods Holding Corporation

Peloton Interactive

LivePerson, Inc.

TreeHouse Foods, Inc.

Comtech Telecommunications Corp.

CytoDyn, Inc.

Blucora, Inc.

Quotient Technology Inc.

NiSource, Inc.

UBS Puerto Rico Family of Funds

Medallion Financial Corp.

UpHealth, Inc.

International Flavors & Fragrances Inc.

Work highlights

  • Representing The New York Times in its activism campaign defense against ValueAct Capital Partners.
  • Represented Hasbro in its successful proxy contest against hedge fund Alta Fox.
  • Represented Box in its successful proxy contest defense against Starboard Value, which was Starboard’s first defeat in a proxy contest in nearly a decade.

Environment > Environment: litigation

Dispute resolution > Appellate: courts of appeals / Appellate: supreme courts (states and federal)

Finance > Structured finance: securitization Tier 2

Insurance > Insurance: non-contentious Tier 2

International Trade > Trade remedies and trade policy Tier 2

Dispute resolution > International arbitration Tier 3

Dispute resolution > Product liability, mass tort and class action - defense: consumer products (including tobacco) Tier 3

Environment > Environment: regulatory Tier 3

Environment > Environment: transactional Tier 3

Finance > Capital markets: debt offerings

Finance > Structured finance: derivatives and structured products Tier 3

International Trade > Customs, export controls and economic sanctions Tier 3

Media, technology and telecoms > Cyber law (including data privacy and data protection) Tier 3

With the May 2022 arrival of David Lashway, John Woods, Jennifer Seale and Jonathan Wilan from Baker McKenzie LLP, Sidley Austin LLP’s Washington DC-centered practice has deepened its expertise in the data privacy and cybersecurity space. The team is called upon to advise leading technology companies and public companies on global and critical malware and ransomware matters that require international regulatory engagement, law enforcement coordination, breach notifications and SEC disclosures. Practice co-heads Alan Charles Raul and Lashway advise clients on global regulatory compliance, data breaches and crisis management with the former focusing on issues concerning national security, constitutional and administrative law. Lashway is also known for his expertise in advising on incident responses to critical infrastructure attacks, national-level misinformation-related issues and data due diligence assistance as part of corporate transactions. Colleen Theresa Brown is the key contact for emerging technology issues, working on the full range of mandates. Clients in the financial sector rely on Woods’ advice concerning global responses to data integrity attacks. Seale brings experience in handling complex cybersecurity investigations. Clayton Northouse departed the firm in April 2022.

Practice head(s):

Alan Charles Raul; David Lashway


‘The team has deep expertise in privacy and cybersecurity and provides great guidance across the board. They have a long history on working with these issues and provide expert guidance on short notice.’

‘Alan Raul has long time deep expertise on cybersecurity and privacy laws stemming from a background in administrative law.

‘Colleen Brown is an excellent privacy attorney working closely with the financial services industry and providing expert advice.’

Key clients

WatchGuard Technologies, Inc.



Securities Industry and Financial Markets Association


Clearlake Capital Group L.P.

nCino, Inc

Work highlights

  • Represented a technology company in a highly sensitive cybersecurity matter regarding the Cyclops Blink malware by a Russian threat actor.
  • Advising AT&T on a broad range of privacy and cybersecurity issues, including advising on communications, satellite and cable privacy, location data privacy, and general privacy under the FTC and Telecom Acts, as well as under state (such as CCPA and CPRA) and international laws.
  • Advising SIFMA on financial privacy, cross-border, cybersecurity, and emerging technology issues.

Media, technology and telecoms > Technology transactions Tier 3

Energy > Energy transactions: oil and gas Tier 4

Finance > Capital markets: equity offerings

Finance > Project finance Tier 4

Healthcare > Life sciences Tier 4

Insurance > Advice to insurers Tier 4

Labor and employment > Employee benefits, executive compensation and retirement plans: transactional Tier 5

M&A/corporate and commercial > Private equity buyouts: large deals ($500m+)

Dispute resolution > Product liability, mass tort and class action - defense: pharmaceuticals and medical devices

Dispute resolution > Product liability, mass tort and class action - defense: toxic tort

Investment fund formation and management > Mutual/registered/exchange-traded funds

Media, technology and telecoms > Telecoms and broadcast: transactions

Media, technology and telecoms > Media and entertainment: transactional

Real estate > Real estate investment trusts (REITs)

Finance > Capital markets: high-yield debt offerings

Latin America: International firms > International arbitration Tier 3

Sidley Austin LLP remains active in both investor-state and commercial arbitrations, most notably in the energy, construction, financial services, mining and real estate sectors. In state representation, the firm has acted for the Republic of Peru in a series of cases, and also has successfully defended the Republic of Colombia. New York and Singapore-based partner Tai-Heng Cheng has represented a number of Asian clients in cases against Latin American states, while New York partner Simon Navarro handles a mix of commercial and investor-state work, particularly in representing Spanish and European clients in energy disputes against Latin American entities. Former (international arbitration) senior managing associate María Carolina Durán and counsel Courtney Hikawa left the firm in August and October 2023, respectively.

Practice head(s):

Tai-Heng Cheng


The Sidley Austin team is discerning, skilled and highly trained.

The Sidley Austin team is without a doubt the best in the business when it comes to investment arbitration. We act as their local partners in various ICSID arbitrations and the quality of their work and dedication to cases is unmatched.

The Sidley Austin team is highly trained to resolve complex issues in complex disputes. Their lawyers are very skilled and understand the perspectives of international arbitration very well.’

Key clients

PACC Offshore Services Holdings (POSH)

TC Energy Corporation

The Republic of Peru

Work highlights

  • Obtained a victory for PACC Offshore Services Holdings (part of the Kuok Group of Singapore), in an investment treaty arbitration against Mexico administered by ICSID under UNCITRAL Rules (ICSID Case No. UNCT/18/5), which concerned the expropriation of the claimant’s investment in the Mexican offshore marine services industry.
  • Represented long-time client the Republic of Peru in successfully limiting the ICSID tribunal’s award to just 5% of the more than $150m in damages sought by Autopista del Norte S.A.C. (AUNOR)  for alleged cost overruns incurred by AUNOR and its subcontractor, OHL Construcción, in relation to the upgrading of a stretch of the Pan-American Highway; the Tribunal agreed with Peru on various aspects of the dispute between the parties regarding the quantification of damages, including the applicable interest rate and the application of taxes.
  • Representing Peru in a pair of parallel ICSID cases brought separately by US (majority) and Netherlands (minority) shareholders in a copper mining project in connection with billions of dollars in taxes imposed on portions of the project; Freeport-McMoRan v. Republic of Peru (ICSID Case No. ARB/20/8) and SMM Cerro Verde v. Republic of Peru (ICSID Case No. ARB/20/14)).

Latin America: International firms > City focus - Miami

Sidley Austin LLP’s launch of a Miami office in July 2022 saw the arrival of the well regarded Juan Delgado and a team, featuring managing associate Axel Miranda, from Morrison Foerster. Prior to becoming part of the firm’s significant move into Miami, the pair already had a track record in Latin America venture capital and emerging company transactions, including investments by SoftBank Latin America Fund; notably, following Delgado’s arrival, the firm was appointed to SoftBank’s outside counsel panel. The team is also noted for corporate restructurings and M&A transactions, with their past experience (prior to joining the firm) including advising SoftBank on a $48m Series B financing for Colombian e-commerce platform Laika, with participation from Delivery Hero, JAM Fund and FJ Labs, and angels Carlos Garcia (Kavak), Emil Michael (Uber) and Pedro Garay (GBM). Further afield, the practice is also active in Brazil, Mexico and other smaller markets in the region.

Practice head(s):

Juan Delgado

Key clients

Grupo Aeroméxico

Avianca Holdings

SoftBank Latin America Fund

Sky Harbour

Work highlights

  • Advised SoftBank in a Series B financing round for Incode, a next-generation identity and authentication platform for global enterprises.

Latin America: International firms > Compliance and investigations

Sidley Austin LLP has a fine reputation in Latin America, including for corporate crime investigations and engagement with US government agencies. It has a long track record in FCPA investigations and is also recognised for sanctions cases. The firm is home to a number of former federal prosecutors and former officials from the DOJ and SEC. The team frequently represents clients in headline investigations by the DOJ and SEC. The Latin America corporate crime team includes New York partners Timothy Treanor and Michael Mann, along with Dallas partners Paige Holden Montgomery and David Silva; Treanor is a former federal prosecutor and is especially active in anti-corruption and white-collar defence work in Latin America, and led the team that represented CONCACAF in the DOJ’s global investigation into corruption in world football.

Practice head(s):

Timothy Treanor; Karen Popp; James Cole; Douglas Axel; David Hoffman; Yuet Ming Tham; Daniel Rubinstein


It is a firm that is characterised by having professionals with outstanding experience and extensive knowledge of law.

In my opinion, Sidley Austin’s Compliance and Investigations practice has a very multi-disciplinary and competent group of lawyers with large experience in different types of enforcement investigations in Latin America. They are used to dealing with different authorities in the context of negotiations.

Tim Treanor and Mike Mann are very experienced lawyers with great ability to understand the client’s issues and address then in the best way possible.

Great level of sophistication, experience, and market awareness.

Michael Mann. A very talented and sophisticated white collar lawyer, highly experienced in dealing with complex cross-border investigations.

Key clients

CONCACAF (The Confederation of North, Central America and Caribbean Association Football)

Bodega Latina Corporation


Grupo Popular


3M Company

Vida Panamá

Exxon Mobil Corporation

Vantage Deepwater Petroleum Company

PACC Offshore Services Holdings

JPMorgan Chase & Company

Franqui Francisco Flores de Freitas

HSBC Monitor

Arthur J Gallagher & Co.

Tyson Foods

Fedex Corporation


Work highlights

  • Represented Stericycle in coordinated settlements resolving FCPA charges with the DOJ and SEC, and local corruption charges with Brazilian authorities.
  • Represented 29 Panamanian entities that have been sanctioned by the Office of Foreign Assets Control (OFAC).
  • Represented CONCACAF in the DOJ’s global investigation into corruption in world football.