The heads of teams within WilmerHale's securities litigation practice, Michael Bongiorno and Matthew Martens, often act for transportation, energy, construction, and education companies. Bongiorno, in New York, regularly acts in securities class action and derivative suits, and Martens is a key contact in the Washington DC practice. Boston-based Timothy Perla has experience defending securities class actions, shareholder derivative lawsuits, insurance, annuity class actions, consumer class actions, and regulatory enforcement matters. Jessica Lewis specializes in class actions and corporate governance disputes from the Palo Alto office. In January 2026, Susan Muck retired as a partner.
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Testimonials
Collated independently by Legal 500 research team.
‘The team came up with very creative solutions to difficult problems, leading to a great result.’
‘Tamar Kaplan-Marans and Mike Bongiorno were very responsive and resolved our litigation very well.’
‘WilmerHale’s Securities Litigation: Defense practice is a market leader in complex, high-stakes matters, combining deep litigation strength with regulatory and enforcement insight. The team includes numerous former senior SEC, DOJ, and judicial officials, giving clients a sophisticated understanding of how regulators and courts operate.’
‘WilmerHale is particularly strong in securities class actions, derivative suits, and parallel SEC and DOJ proceedings, including matters involving accounting, disclosure, SPACs, and emerging ESG issues. WilmerHale’s securities litigators work seamlessly with regulatory, investigations, appellate, and cybersecurity teams, while offering billing flexibility where appropriate and maintaining a strong, longstanding commitment to diversity, inclusion, and talent development.’
‘The individuals we work with stand out for their excellent judgment, responsiveness, and practical approach, particularly in complex securities matters. They are effective at translating technical, legal, and regulatory issues into clear, actionable advice.’
- ‘Mike Bongiorno is recognized for his analytical rigor, responsiveness, and hands-on management of complex cases, making him a trusted and effective day-to-day adviser. Peter Kolovos is highly valued for his strategic leadership and deep experience in securities litigation, bringing calm, commercially focused judgment to high-stakes matters. Across the team, both partners and associates are consistently collaborative, well-prepared, and strongly client-focused.’
Key clients
- Zymergen Inc.
- Plantronics
- Velodyne Lidar, Inc.
- Sonder Holdings Inc.
- Life Insurance Company of the Southwest
- Former Chief Auditor of Wells Fargo
- Biogen Inc.
- Zuora, Inc.
- Independent Directors of SVB Financial Group
- Audit Committee of Equinix, Inc.
- Digimarc Corporation
- Tapestry, Inc.
Work highlights
Representing current and former directors of Silicon Valley Bank (SVB) and its holding company, SVB Financial Group (SVBFG), in multiple lawsuits and regulatory proceedings arising from SVB’s collapse in March 2023.
Representing Norfolk Southern and certain of its current and former officers and directors in a securities fraud class action arising out of a train derailment in Ohio.
Representing the directors of Zymergen Inc., a life science automation platform company, in multiple matters stemming from its initial public offering, including a securities class action litigation pending in the United States District Court for the Northern District of California.
Lawyers
Leading partners
The strongest partners in their field, leading on market-leading deals and endorsed by peers and clients alike.
Next Generation Partners
Junior partners with significant recognition from clients and peers in the market and key roles on multiple matters.
Practice head
Michael Bongiorno; Matthew Martens
Other key lawyers
Susan Muck; Kevin Muck; Timothy Perla; Fraser Hunter, Jr.; Andrew Rhys Davies; Jessica Lewis; Tamar Kaplan-Marans; Robert Kingsley Smith