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Trademark and Advertising

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  • Unmatched Experience Scaling Technology and Life Science Brands

    We have guided an extraordinary number of tech and life science businesses on issues ranging from trademark clearance and prosecution to complex transactions and high-stakes litigation in courts across the U.S. and in other countries.  Our attorneys offer strategic advice as companies establish their identities during early stages of growth and as they expand their activities and scale their brands across markets.

  • Pragmatic Advice

    We offer pragmatic advice to enterprises on selection and protection of business and product names; advertising campaigns; disputes and regulatory matters; domain name and social media issues; labeling and packaging; retail and consumer protection laws; contests and sweepstakes; unfair competition; IP transactions; and personal publicity rights.

  • Extensive Copyright Expertise

    Our attorneys counsel clients on cutting-edge issues related to copyright protection, including content licensing and content ownership agreements, software licensing agreements, printed works for consumer and commercial use, statutory exemptions and licenses, fair use, reproduction agreements, and derivative works, distribution, and public performance rights. The firm has exceptional experience litigating cutting-edge copyright issues and counseling on digital exploitation of copyrighted content.

  • Advocacy and Dispute Resolution

    We routinely represent clients in trademark, copyright and advertising disputes, including in courts across the U.S., before the U.S. Patent and Trademark Office and before government offices around the world. We also have significant experience in proceedings before the National Advertising Division of the Better Business Bureau (NAD) and in FTC and state regulatory investigations.

Business success can be driven by the strength and vitality of a company’s marketplace identity. We partner with businesses and organizations to develop sophisticated strategies to build and grow brands and marketing content.  We work closely with a trusted network of global counsel to guide our clients internationally. 

We counsel clients in numerous fields, including e-commerce, consumer products, computer software and hardware, life sciences, medical devices, healthcare, automotive and transportation services, finance, gaming, entertainment, and sports.  Our clients range from growth-minded start-ups to multinational companies with operations and customers around the world.  We work routinely with disruptors seeking to convert game-changing ideas into world-changing products and rare skills into innovative services.

Our attorneys are recognized among the leading practitioners in their fields by publications such as Chambers Global, Chambers USA, The American Lawyer, World Trademark Review, The Daily Journal and others.

Among the issues that we advise on are:

  • Brand selection, enforcement, and defense
  • Development of intellectual property portfolios
  • Licenses and transfers of intellectual property
  • Internet and social media liability issues
  • Domain names
  • Trade dress
  • Advertising and marketing campaigns
  • Promotions, contests and sweepstakes
  • Fair use of trademarks and copyrighted content
  • False advertising
  • Consumer protection issues

We assist clients with all forms of media and copyrightable works, including digital content, audiovisual presentations, software, film, literature, images, photography, and recorded music and sounds. Our attorneys have substantial copyright law experience in conjunction with both commercial transactions and licensing. 

We regularly work with clients on commercial transactions and agreements driven by brands, content and advertising, including strategic alliances, partnerships, and joint ventures; asset sales and spinouts; content and trademark licenses; and advertising and PR agency agreements, among others.

Our attorneys have also achieved exceptional results in trademark and copyright litigation, including in bet-the-brand cases. We have considerable experience in forums where intellectual property and false advertising cases are often litigated, such as the Trademark Trial and Appeal Board, federal district courts and appellate courts, and the National Advertising Division of the Better Business Bureau (NAD).

Overview

Business success can be driven by the strength and vitality of a company’s marketplace identity. We partner with businesses and organizations to develop sophisticated strategies to build and grow brands and marketing content.  We work closely with a trusted network of global counsel to guide our clients internationally. 

We counsel clients in numerous fields, including e-commerce, consumer products, computer software and hardware, life sciences, medical devices, healthcare, automotive and transportation services, finance, gaming, entertainment, and sports.  Our clients range from growth-minded start-ups to multinational companies with operations and customers around the world.  We work routinely with disruptors seeking to convert game-changing ideas into world-changing products and rare skills into innovative services.

Our attorneys are recognized among the leading practitioners in their fields by publications such as Chambers Global, Chambers USA, The American Lawyer, World Trademark Review, The Daily Journal and others.

Among the issues that we advise on are:

  • Brand selection, enforcement, and defense
  • Development of intellectual property portfolios
  • Licenses and transfers of intellectual property
  • Internet and social media liability issues
  • Domain names
  • Trade dress
  • Advertising and marketing campaigns
  • Promotions, contests and sweepstakes
  • Fair use of trademarks and copyrighted content
  • False advertising
  • Consumer protection issues

We assist clients with all forms of media and copyrightable works, including digital content, audiovisual presentations, software, film, literature, images, photography, and recorded music and sounds. Our attorneys have substantial copyright law experience in conjunction with both commercial transactions and licensing. 

We regularly work with clients on commercial transactions and agreements driven by brands, content and advertising, including strategic alliances, partnerships, and joint ventures; asset sales and spinouts; content and trademark licenses; and advertising and PR agency agreements, among others.

Our attorneys have also achieved exceptional results in trademark and copyright litigation, including in bet-the-brand cases. We have considerable experience in forums where intellectual property and false advertising cases are often litigated, such as the Trademark Trial and Appeal Board, federal district courts and appellate courts, and the National Advertising Division of the Better Business Bureau (NAD).

Client Highlights
Wilson Sonsini Advises Centessa on IP Matters Related to Acquisition by Lilly
On March 31, 2026, Centessa Pharmaceuticals, a clinical-stage company developing a new class of medicines for the treatment of excessive daytime sleepiness and other neurological conditions, announced a definitive agreement for Eli Lilly and Company (Lilly), an American multinational pharmaceutical company, to acquire Centessa. Under the terms of the transaction agreement, Lilly will acquire all of the issued and to be issued share capital of Centessa (including the American Depositary Shares (ADSs) representing ordinary shares) for $38.00 in cash per share plus one non-transferrable contingent value right (CVR) that entitles the holder to receive up to an aggregate of $9.00 subject to the achievement of three milestones described below, for total potential aggregate per share consideration of up to $47.00. The upfront cash consideration represents an aggregate equity value of approximately $6.3 billion and the CVR represents an additional potential aggregate equity value of approximately $1.5 billion. Wilson Sonsini Goodrich & Rosati advised Centessa in IP matters related to the transaction.
News Articles
2026 Chambers Global Guide Recognizes Wilson Sonsini, Attorneys
On February 12, 2026, Chambers and Partners recognized Wilson Sonsini practices and attorneys among the top global lawyers, law firms, and in-house counsel in over 200 jurisdictions in the 2026 edition of its Chambers Global guide. The listings were compiled based on confidential interviews with attorneys and law firm clients to assess firms, practice groups, and individual attorneys based on their technical legal ability, professional conduct, client service, commercial astuteness, diligence, commitment, and other valued qualities.
News Articles
2026 WTR 1000 Honors Wilson Sonsini’s Trademark Practice, Attorneys
Wilson Sonsini Goodrich & Rosati’s trademark and advertising practice has been ranked among the leading firms in the 2026 edition of World Trademark Review’s WTR 1000, an annual guide that showcases the top trademark professionals across key jurisdictions worldwide. The firm is recognized as a leader in both California and Washington.
Newsletters
Litigation Trends to Watch in 2026
Entering 2026, Wilson Sonsini litigators see a landscape defined by AI driven disputes, continued tightening of patent review standards, renewed securities and governance litigation, stronger consumer and influencer enforcement, and escalating Telephone Consumer Protection Act (TCPA) exposure—trends that require companies to align legal strategy with technical and operational controls.
Alerts
Inventor’s Failure to Provide Material Information to the USPTO Results in an Unenforceable Patent
On August 20, 2025, the U.S. District Court for the District of Delaware (court) found inequitable conduct when Applicant, Lindis Biotech, GMBH (Lindis), relied on data from hastily performed experiments to obtain a patent from the United States Patent and Trademark Office (USPTO), while withholding from the USPTO more thorough contradictory data.
News Articles
Wilson Sonsini’s Trademark Practice, Attorneys Recognized in 2025 World Trademark Review 1000
Wilson Sonsini Goodrich & Rosati’s trademark and advertising practice has been ranked in the 2025 edition of World Trademark Review’s WTR 1000, an annual guide that highlights the top trademark professionals in key jurisdictions worldwide. Wilson Sonsini is recognized as a leading firm in Washington.
View All
Insights
Client Highlights
Wilson Sonsini Advises Centessa on IP Matters Related to Acquisition by Lilly
On March 31, 2026, Centessa Pharmaceuticals, a clinical-stage company developing a new class of medicines for the treatment of excessive daytime sleepiness and other neurological conditions, announced a definitive agreement for Eli Lilly and Company (Lilly), an American multinational pharmaceutical company, to acquire Centessa. Under the terms of the transaction agreement, Lilly will acquire all of the issued and to be issued share capital of Centessa (including the American Depositary Shares (ADSs) representing ordinary shares) for $38.00 in cash per share plus one non-transferrable contingent value right (CVR) that entitles the holder to receive up to an aggregate of $9.00 subject to the achievement of three milestones described below, for total potential aggregate per share consideration of up to $47.00. The upfront cash consideration represents an aggregate equity value of approximately $6.3 billion and the CVR represents an additional potential aggregate equity value of approximately $1.5 billion. Wilson Sonsini Goodrich & Rosati advised Centessa in IP matters related to the transaction.
News Articles
2026 Chambers Global Guide Recognizes Wilson Sonsini, Attorneys
On February 12, 2026, Chambers and Partners recognized Wilson Sonsini practices and attorneys among the top global lawyers, law firms, and in-house counsel in over 200 jurisdictions in the 2026 edition of its Chambers Global guide. The listings were compiled based on confidential interviews with attorneys and law firm clients to assess firms, practice groups, and individual attorneys based on their technical legal ability, professional conduct, client service, commercial astuteness, diligence, commitment, and other valued qualities.
News Articles
2026 WTR 1000 Honors Wilson Sonsini’s Trademark Practice, Attorneys
Wilson Sonsini Goodrich & Rosati’s trademark and advertising practice has been ranked among the leading firms in the 2026 edition of World Trademark Review’s WTR 1000, an annual guide that showcases the top trademark professionals across key jurisdictions worldwide. The firm is recognized as a leader in both California and Washington.
Newsletters
Litigation Trends to Watch in 2026
Entering 2026, Wilson Sonsini litigators see a landscape defined by AI driven disputes, continued tightening of patent review standards, renewed securities and governance litigation, stronger consumer and influencer enforcement, and escalating Telephone Consumer Protection Act (TCPA) exposure—trends that require companies to align legal strategy with technical and operational controls.
Alerts
Inventor’s Failure to Provide Material Information to the USPTO Results in an Unenforceable Patent
On August 20, 2025, the U.S. District Court for the District of Delaware (court) found inequitable conduct when Applicant, Lindis Biotech, GMBH (Lindis), relied on data from hastily performed experiments to obtain a patent from the United States Patent and Trademark Office (USPTO), while withholding from the USPTO more thorough contradictory data.
News Articles
Wilson Sonsini’s Trademark Practice, Attorneys Recognized in 2025 World Trademark Review 1000
Wilson Sonsini Goodrich & Rosati’s trademark and advertising practice has been ranked in the 2025 edition of World Trademark Review’s WTR 1000, an annual guide that highlights the top trademark professionals in key jurisdictions worldwide. Wilson Sonsini is recognized as a leading firm in Washington.
View All
Speaking Engagements
USC Gould School of Law 2026 Intellectual Property Institute
Wilson Sonsini is proud to sponsor the USC Gould School of Law 2026 Intellectual Property Institute. Join other IP professionals for a gathering of national speakers and a sophisticated discussion of emerging issues and best practices in copyright, patent, trademark, trade secret and related fields. The Intellectual Property Institute has forged a reputation for gathering national speakers to analyze sophisticated topics and provide practical takeaways. Focusing on copyright, patent and trademark law, the Institute takes place over the course of two days at The Fairmont Miramar Hotel & Bungalows in Santa Monica and features morning plenary sessions, a keynote address, and tracked sessions. Visit the event website to learn more.
Speaking Engagements
Association of Corporate Counsel San Francisco Bay Area CLE: How to Counsel Your Marketing Department (San Francisco)
In-house counsel are invited to join Wilson Sonsini attorneys Alyssa Worsham and Christine Au-Yeung for an ACC San Francisco Bay Area CLE program titled “Marketing 101: How to Counsel Your Marketing Department” in San Francisco on Wednesday, October 30. Alyssa and Christine will be joined by Stephanie Hall, Director of Trademark & Brand at Lyft, and will discuss how to be an effective legal voice to your marketing and brand teams as they launch innovative products on a global scale, embrace opportunities in social media, and leverage influencers and endorsements in their marketing initiatives. The program will also cover new FTC rules on using reviews and testimonials in marketing and ways to promote brands through sweepstakes and contests.  
Speaking Engagements
Association of Corporate Counsel San Francisco Bay Area CLE: How to Counsel Your Marketing Department (Palo Alto)
In-house counsel are invited to join Wilson Sonsini attorneys Alyssa Worsham and Christine Au-Yeung for an ACC San Francisco Bay Area CLE program titled “Marketing 101: How to Counsel Your Marketing Department” in Palo Alto on Tuesday, October 29. Alyssa and Christine will be joined by Stephanie Hall, Director of Trademark & Brand at Lyft, and will discuss how to be an effective legal voice to your marketing and brand teams as they launch innovative products on a global scale, embrace opportunities in social media, and leverage influencers and endorsements in their marketing initiatives. The program will also cover new FTC rules on using reviews and testimonials in marketing and ways to promote brands through sweepstakes and contests.  
WSGR Events
Wilson Sonsini’s 31st Annual Medical Device & Digital Health Conference
Wilson Sonsini Goodrich & Rosati’s 31st Annual Medical Device & Digital Health Conference will address topics of critical importance to medical device and digital health companies today, including key healthcare regulatory considerations, the relationship between intellectual property and valuation, a look back at 2023’s fundraising and deals, and how 2024 is shaping up along with partnering strategies in the current market.
Affiliated Programs
Los Angeles Intellectual Property Law Association - Washington in the West
Now in its 30th year, Washington in the West is an MCLE-accredited event featuring sessions for patent and trademark attorneys. Wilson Sonsini is pleased to serve as a sponsor for this event which includes a keynote speech by Mary Fuller, Regional Director of the USPTO’s Silicon Valley Regional Office.
WSGR Events
Digital Health Webinar Series - Marketing and Advertising for Digital Health Companies
On Wednesday, December 6th, Wilson Sonsini is pleased to host the fifth session in our Digital Health Webinar Series.
View All
Events
Speaking Engagements
USC Gould School of Law 2026 Intellectual Property Institute
Wilson Sonsini is proud to sponsor the USC Gould School of Law 2026 Intellectual Property Institute. Join other IP professionals for a gathering of national speakers and a sophisticated discussion of emerging issues and best practices in copyright, patent, trademark, trade secret and related fields. The Intellectual Property Institute has forged a reputation for gathering national speakers to analyze sophisticated topics and provide practical takeaways. Focusing on copyright, patent and trademark law, the Institute takes place over the course of two days at The Fairmont Miramar Hotel & Bungalows in Santa Monica and features morning plenary sessions, a keynote address, and tracked sessions. Visit the event website to learn more.
Speaking Engagements
Association of Corporate Counsel San Francisco Bay Area CLE: How to Counsel Your Marketing Department (San Francisco)
In-house counsel are invited to join Wilson Sonsini attorneys Alyssa Worsham and Christine Au-Yeung for an ACC San Francisco Bay Area CLE program titled “Marketing 101: How to Counsel Your Marketing Department” in San Francisco on Wednesday, October 30. Alyssa and Christine will be joined by Stephanie Hall, Director of Trademark & Brand at Lyft, and will discuss how to be an effective legal voice to your marketing and brand teams as they launch innovative products on a global scale, embrace opportunities in social media, and leverage influencers and endorsements in their marketing initiatives. The program will also cover new FTC rules on using reviews and testimonials in marketing and ways to promote brands through sweepstakes and contests.  
Speaking Engagements
Association of Corporate Counsel San Francisco Bay Area CLE: How to Counsel Your Marketing Department (Palo Alto)
In-house counsel are invited to join Wilson Sonsini attorneys Alyssa Worsham and Christine Au-Yeung for an ACC San Francisco Bay Area CLE program titled “Marketing 101: How to Counsel Your Marketing Department” in Palo Alto on Tuesday, October 29. Alyssa and Christine will be joined by Stephanie Hall, Director of Trademark & Brand at Lyft, and will discuss how to be an effective legal voice to your marketing and brand teams as they launch innovative products on a global scale, embrace opportunities in social media, and leverage influencers and endorsements in their marketing initiatives. The program will also cover new FTC rules on using reviews and testimonials in marketing and ways to promote brands through sweepstakes and contests.  
WSGR Events
Wilson Sonsini’s 31st Annual Medical Device & Digital Health Conference
Wilson Sonsini Goodrich & Rosati’s 31st Annual Medical Device & Digital Health Conference will address topics of critical importance to medical device and digital health companies today, including key healthcare regulatory considerations, the relationship between intellectual property and valuation, a look back at 2023’s fundraising and deals, and how 2024 is shaping up along with partnering strategies in the current market.
Affiliated Programs
Los Angeles Intellectual Property Law Association - Washington in the West
Now in its 30th year, Washington in the West is an MCLE-accredited event featuring sessions for patent and trademark attorneys. Wilson Sonsini is pleased to serve as a sponsor for this event which includes a keynote speech by Mary Fuller, Regional Director of the USPTO’s Silicon Valley Regional Office.
WSGR Events
Digital Health Webinar Series - Marketing and Advertising for Digital Health Companies
On Wednesday, December 6th, Wilson Sonsini is pleased to host the fifth session in our Digital Health Webinar Series.
View All
Aaron D. Hendelman
Partner
Seattle
Aaron heads the firm's trademark and advertising practice, focusing on the areas of trademark, advertising, unfair competition, copyright, retail, rights of publicity, social media, and consumer law.
  • Trademark and Advertising
View Profile
Alyssa M. Worsham
Partner
Seattle
Alyssa Worsham is a member of the firm’s trademark and advertising team, which has been recognized in Chambers and Partners’ USA and Global guides, as well as World Trademark Review’s WTR 1000. She focuses on global strategic advice, litigation strategy, and transactional guidance for clients’ trademarks, branding, and advertising in marketplaces where commercial and geographic lines are increasingly blurring. She helps clients assess the risk in selecting new business and product names, and works with them to build, exploit, and protect these names creatively and strategically. Alyssa advises on trademark disputes, domain name disputes, contests and sweepstakes, advertising review, right of publicity, social media issues, Telephone Consumer Protection Act (TCPA) compliance (i.e., the rules surrounding marketing texts and calls), FTC compliance and investigations, copyright, IP diligence, and associated commercial contracts. She works with software companies, biotech start-ups, cosmetics companies, fashion companies, life sciences and digital health companies, agro-tech companies, consumer products, non-profits, and game developers, among others. She advises founders, CEOs, GCs, IP specialists, and chief marketing officers on the critical issues surrounding brand creation, protection, and strategy.
  • Trademark and Advertising
View Profile
Christine K. Au-Yeung
Partner
San Francisco
Christine Au-Yeung is a partner in the San Francisco and Palo Alto offices of Wilson Sonsini Goodrich & Rosati, where she specializes in trademark, copyright, and advertising law. She counsels clients on all aspects of brand protection in the U.S. and throughout the world, including clearance and selection of trademarks, prosecution of trademark applications, licensing, and the resolution of trademark infringement and domain name disputes. She also advises clients on advertising issues, including TCPA compliance related to marketing calls and texts as well as strategies on promotions such as sweepstakes and contests.
  • Trademark and Advertising
View Profile
Brandon P. Leahy
Senior Counsel
San Francisco
Brandon Leahy is senior counsel in the San Francisco office of Wilson Sonsini Goodrich & Rosati, where he practices trademark, copyright, and advertising law. He advises clients on all aspects of brand protection and enforcement in the U.S. and internationally, including clearance and selection of trademarks, prosecution of trademark applications, and licensing and transactions. He also represents clients in federal court litigation, in disputes before the Trademark Trial and Appeal Board, and in arbitration proceedings involving domain names.
  • Trademark and Advertising
View Profile
John P. Flynn
Partner
San Francisco
John is a veteran trial lawyer with 30 years of experience in high-stakes, enterprise-threatening corporate and commercial litigation.
  • Litigation
View Profile
Daniel Glazer
Partner
London
Daniel counsels UK and European tech and life sciences companies on U.S. expansion and fundraising.
  • Corporate
View Profile
Gary R. Greenstein
Partner
Washington, D.C.
Gary represents companies in transactions with record labels, music publishers, and program suppliers focusing on intellectual property, licensing, and commercial transactions.
  • Technology Transactions
View Profile
Maura L. Rees
Partner
Palo Alto
Maura is an experienced litigator who represents clients in complex commercial litigation and IP-related disputes, including copyright, trademark, patent, and antitrust matters, as well as consumer class actions.
  • Litigation
View Profile
Brian M. Willen
Partner
New York
Brian represents companies facing challenging disputes involving novel issues of law. 
  • Litigation
View Profile
John L. Slafsky
Partner Emeritus
John Slafsky retired as partner at Wilson Sonsini in 2025.
  • Trademark and Advertising
View Profile
View All
People
Aaron D. Hendelman
Partner
Seattle
Aaron heads the firm's trademark and advertising practice, focusing on the areas of trademark, advertising, unfair competition, copyright, retail, rights of publicity, social media, and consumer law.
  • Trademark and Advertising
View Profile
Alyssa M. Worsham
Partner
Seattle
Alyssa Worsham is a member of the firm’s trademark and advertising team, which has been recognized in Chambers and Partners’ USA and Global guides, as well as World Trademark Review’s WTR 1000. She focuses on global strategic advice, litigation strategy, and transactional guidance for clients’ trademarks, branding, and advertising in marketplaces where commercial and geographic lines are increasingly blurring. She helps clients assess the risk in selecting new business and product names, and works with them to build, exploit, and protect these names creatively and strategically. Alyssa advises on trademark disputes, domain name disputes, contests and sweepstakes, advertising review, right of publicity, social media issues, Telephone Consumer Protection Act (TCPA) compliance (i.e., the rules surrounding marketing texts and calls), FTC compliance and investigations, copyright, IP diligence, and associated commercial contracts. She works with software companies, biotech start-ups, cosmetics companies, fashion companies, life sciences and digital health companies, agro-tech companies, consumer products, non-profits, and game developers, among others. She advises founders, CEOs, GCs, IP specialists, and chief marketing officers on the critical issues surrounding brand creation, protection, and strategy.
  • Trademark and Advertising
View Profile
Christine K. Au-Yeung
Partner
San Francisco
Christine Au-Yeung is a partner in the San Francisco and Palo Alto offices of Wilson Sonsini Goodrich & Rosati, where she specializes in trademark, copyright, and advertising law. She counsels clients on all aspects of brand protection in the U.S. and throughout the world, including clearance and selection of trademarks, prosecution of trademark applications, licensing, and the resolution of trademark infringement and domain name disputes. She also advises clients on advertising issues, including TCPA compliance related to marketing calls and texts as well as strategies on promotions such as sweepstakes and contests.
  • Trademark and Advertising
View Profile
Brandon P. Leahy
Senior Counsel
San Francisco
Brandon Leahy is senior counsel in the San Francisco office of Wilson Sonsini Goodrich & Rosati, where he practices trademark, copyright, and advertising law. He advises clients on all aspects of brand protection and enforcement in the U.S. and internationally, including clearance and selection of trademarks, prosecution of trademark applications, and licensing and transactions. He also represents clients in federal court litigation, in disputes before the Trademark Trial and Appeal Board, and in arbitration proceedings involving domain names.
  • Trademark and Advertising
View Profile
John P. Flynn
Partner
San Francisco
John is a veteran trial lawyer with 30 years of experience in high-stakes, enterprise-threatening corporate and commercial litigation.
  • Litigation
View Profile
Daniel Glazer
Partner
London
Daniel counsels UK and European tech and life sciences companies on U.S. expansion and fundraising.
  • Corporate
View Profile
Gary R. Greenstein
Partner
Washington, D.C.
Gary represents companies in transactions with record labels, music publishers, and program suppliers focusing on intellectual property, licensing, and commercial transactions.
  • Technology Transactions
View Profile
Maura L. Rees
Partner
Palo Alto
Maura is an experienced litigator who represents clients in complex commercial litigation and IP-related disputes, including copyright, trademark, patent, and antitrust matters, as well as consumer class actions.
  • Litigation
View Profile
Brian M. Willen
Partner
New York
Brian represents companies facing challenging disputes involving novel issues of law. 
  • Litigation
View Profile
John L. Slafsky
Partner Emeritus
John Slafsky retired as partner at Wilson Sonsini in 2025.
  • Trademark and Advertising
View Profile
View All
Related Practices
  • Internet Strategy and Litigation
  • Technology Transactions
  • Trademark and Copyright Litigation
Related Industries
  • Communications and Networking
  • Consumer Products and Services
  • Digital Media and Entertainment
  • Electronic Gaming
  • Financial Services
  • Life Sciences
  • Mobility
  • Software
Recent Insights
Client Highlights
Wilson Sonsini Advises Centessa on IP Matters Related to Acquisition by Lilly
On March 31, 2026, Centessa Pharmaceuticals, a clinical-stage company developing a new class of medicines for the treatment of excessive daytime sleepiness and other neurological conditions, announced a definitive agreement for Eli Lilly and Company (Lilly), an American multinational pharmaceutical company, to acquire Centessa. Under the terms of the transaction agreement, Lilly will acquire all of the issued and to be issued share capital of Centessa (including the American Depositary Shares (ADSs) representing ordinary shares) for $38.00 in cash per share plus one non-transferrable contingent value right (CVR) that entitles the holder to receive up to an aggregate of $9.00 subject to the achievement of three milestones described below, for total potential aggregate per share consideration of up to $47.00. The upfront cash consideration represents an aggregate equity value of approximately $6.3 billion and the CVR represents an additional potential aggregate equity value of approximately $1.5 billion. Wilson Sonsini Goodrich & Rosati advised Centessa in IP matters related to the transaction.
Learn More
News Articles
2026 Chambers Global Guide Recognizes Wilson Sonsini, Attorneys
On February 12, 2026, Chambers and Partners recognized Wilson Sonsini practices and attorneys among the top global lawyers, law firms, and in-house counsel in over 200 jurisdictions in the 2026 edition of its Chambers Global guide. The listings were compiled based on confidential interviews with attorneys and law firm clients to assess firms, practice groups, and individual attorneys based on their technical legal ability, professional conduct, client service, commercial astuteness, diligence, commitment, and other valued qualities.
Learn More
View All
Recent Events
Speaking Engagements
USC Gould School of Law 2026 Intellectual Property Institute
Wilson Sonsini is proud to sponsor the USC Gould School of Law 2026 Intellectual Property Institute. Join other IP professionals for a gathering of national speakers and a sophisticated discussion of emerging issues and best practices in copyright, patent, trademark, trade secret and related fields. The Intellectual Property Institute has forged a reputation for gathering national speakers to analyze sophisticated topics and provide practical takeaways. Focusing on copyright, patent and trademark law, the Institute takes place over the course of two days at The Fairmont Miramar Hotel & Bungalows in Santa Monica and features morning plenary sessions, a keynote address, and tracked sessions. Visit the event website to learn more.
Learn More
Speaking Engagements
Association of Corporate Counsel San Francisco Bay Area CLE: How to Counsel Your Marketing Department (San Francisco)
In-house counsel are invited to join Wilson Sonsini attorneys Alyssa Worsham and Christine Au-Yeung for an ACC San Francisco Bay Area CLE program titled “Marketing 101: How to Counsel Your Marketing Department” in San Francisco on Wednesday, October 30. Alyssa and Christine will be joined by Stephanie Hall, Director of Trademark & Brand at Lyft, and will discuss how to be an effective legal voice to your marketing and brand teams as they launch innovative products on a global scale, embrace opportunities in social media, and leverage influencers and endorsements in their marketing initiatives. The program will also cover new FTC rules on using reviews and testimonials in marketing and ways to promote brands through sweepstakes and contests.  
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Key Contacts
Christine K. Au-Yeung
Partner
San Francisco
Christine Au-Yeung is a partner in the San Francisco and Palo Alto offices of Wilson Sonsini Goodrich & Rosati, where she specializes in trademark, copyright, and advertising law. She counsels clients on all aspects of brand protection in the U.S. and throughout the world, including clearance and selection of trademarks, prosecution of trademark applications, licensing, and the resolution of trademark infringement and domain name disputes. She also advises clients on advertising issues, including TCPA compliance related to marketing calls and texts as well as strategies on promotions such as sweepstakes and contests.
  • Trademark and Advertising
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Aaron D. Hendelman
Partner
Seattle
Aaron heads the firm's trademark and advertising practice, focusing on the areas of trademark, advertising, unfair competition, copyright, retail, rights of publicity, social media, and consumer law.
  • Trademark and Advertising
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Alyssa M. Worsham
Partner
Seattle
Alyssa Worsham is a member of the firm’s trademark and advertising team, which has been recognized in Chambers and Partners’ USA and Global guides, as well as World Trademark Review’s WTR 1000. She focuses on global strategic advice, litigation strategy, and transactional guidance for clients’ trademarks, branding, and advertising in marketplaces where commercial and geographic lines are increasingly blurring. She helps clients assess the risk in selecting new business and product names, and works with them to build, exploit, and protect these names creatively and strategically. Alyssa advises on trademark disputes, domain name disputes, contests and sweepstakes, advertising review, right of publicity, social media issues, Telephone Consumer Protection Act (TCPA) compliance (i.e., the rules surrounding marketing texts and calls), FTC compliance and investigations, copyright, IP diligence, and associated commercial contracts. She works with software companies, biotech start-ups, cosmetics companies, fashion companies, life sciences and digital health companies, agro-tech companies, consumer products, non-profits, and game developers, among others. She advises founders, CEOs, GCs, IP specialists, and chief marketing officers on the critical issues surrounding brand creation, protection, and strategy.
  • Trademark and Advertising
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