BakerHostetler

Firm overview:

BakerHostetler manages a substantial patent prosecution practice, with more than 13,000 patent applications under its supervision, making it a go-to choice for clients seeking broad prosecution support across disciplines including chemical, computer science, electrical, mechanical and pharmaceutical. The firm’s prosecution team includes approximately 75 patent attorneys who work with a range of clients from large corporations to emerging innovators.

The firm has demonstrated its capacity for large-scale patent work by managing extensive portfolios for major clients, including handling over 1,000 patent filings across more than 20 divisions of a precision equipment manufacturer and prosecuting hundreds of applications for a multinational software technology company in recent years.

In addition to strong prosecution capabilities, BakerHostetler maintains a robust litigation bench of patent trial lawyers and registered practitioners who defend and enforce clients’ patent rights in courts and before administrative tribunals. Clients have commended the firm’s ability to successfully defend patents in inter partes review proceedings at the US Patent and Trademark Office (USPTO), noting clear communication and effective strategy.

Team overview:

At the leadership level, Timothy Casey serves as a key IP partner, drawing on more than 30 years of experience in patent prosecution, technology transactions and IP strategy. Casey’s background in managing worldwide patent filings supports clients in complex technology areas and broader enterprise-level IP planning.

Theresa Weisenberger co-leads the firm’s intellectual property and technology transactions practices and its AI cross-practice team from the Atlanta office. She advises clients on emerging technologies and integrates IP protection with broader business objectives.

Leif Sigmond Jr remains a central figure in the firm’s patent litigation practice, with decades of experience handling disputes involving software and complex technologies. He also co-chairs the Patent Litigation Group and leads the Software Industry Group.

Jason Hoffman continues to be a standout IP litigator based in Washington, DC, known for his courtroom success and appellate work. Hoffman also contributes to the firm’s annual ‘One Year of Patent Law’ webinar, highlighting important Federal Circuit and Supreme Court decisions.

Robert (Bob) Hails remains active in the firm’s Washington DC litigation team, focusing on high-stakes patent infringement matters in electrical engineering and related disciplines.

Jeffrey Lesovitz is based in Philadelphia and represents clients across sectors such as consumer electronics, semiconductor, software and medical devices. He has significant experience with ITC Section 337 investigations and other contentious proceedings.

A significant departure from the team in 2025 was that of patent attorney Cory Davis, who is now a partner at Seyfarth Shaw.

Key matters:

• Patent portfolio management and prosecution for Meta Platforms

BakerHostetler advises Meta Platforms, formerly Facebook, which owns Facebook, Instagram, and WhatsApp and is one of the world’s most valuable companies.

BakerHostetler has advised Meta on AI and machine learning technology inventions involving Meta AI as well as virtual reality (VR), augmented reality (AR), and mixed reality (MR) technology; this includes Meta’s VR/AR/MR headsets, smart glasses and Meta Quest headsets.

The prosecution team has handled significant portfolios of Meta’s patent inventory, and are one of Meta’s go-to counsel handling some of Meta’s important technology focus areas, for example, involving Meta AI.

Clients:

Aerion, Asphalt System, Blackhawk Network, BoozAllenHamilton, Brumfield, Chestek, Comcast, Dragonfly Endscopy, Hewlett-Packard, IGT, Klas Group, L3 Harris Technologies, Lockheed Martin, Meta, Nordson, Reliant Value, ServiceTitan, Siemens Gamesa Renewable Energy, Sony, Syngenta, TomTom, Top Product Innovations, Trading Technologies International, Transdigm Group, USAA, Vrise Therapeutics, Wolfspeed, Xencor.