John Sellers

Senior Counsel
jsellers@cooley.com
Full contact info

I represent emerging companies and their investors at all stages, from new startup to world class public companies. I’m passionate about being part of disruptive new technologies.

About John

John focuses on representing emerging and public growth companies and the venture capital firms that invest in them. John counsels companies throughout their life cycle on a full range of matters, including company formations, VC financings, initial public and follow-on public offerings, corporate governance, mergers and acquisitions, strategic partnership and licensing transactions, Securities and Exchange Commission reporting and compliance, and day-to-day corporate counseling.

View full bio

Experience

Jocasta Neuroscience Secures $35 Million Series A

Jocasta Neuroscience Secures $35 Million Series A

August 12, 2025

Cooley advised Jocasta Neuroscience, a preclinical-stage, longevity-focused company, on its $35 million Series A financing. Its lead asset, a proprietary formulation of the longevity protein a - Klotho, is used to treat a range of conditions, including cognitive impairment in neurodegenerative diseases.

Read more

Related contacts

Gregory S. Grossman
Partner, Chicago
Briana Yesilli
Associate, Chicago
Adam Bloom
Associate, Chicago
Caitlin Courtney
Partner, Palo Alto
John Sellers
Senior Counsel, Palo Alto
Rebecca Ross
Special Counsel, Washington, DC
Mateus Kaba Aboud
Associate, Chicago

Related Practices & Industries

Emerging Companies
Technology Transactions
Life Sciences
Healthcare

Hadrian Secures $260 Million Series C

Hadrian Secures $260 Million Series C

July 17, 2025

Cooley advised Hadrian, a manufacturing company building artificial intelligence-powered factories for America, on its $260 million Series C financing round.

Read more

Related contacts

Peter H. Werner
Partner in Charge – San Francisco, San Francisco
Emma E. Mann-Meginniss
Partner, San Francisco
Michael Tollini
Partner, Washington, DC
Ellie Seber
Partner, Santa Monica
Zander Olsson
Associate, San Francisco
Carl Min
Associate, San Francisco
Erin Wright
Associate, San Francisco
Kavi Huded
Associate, New York
David Shekman
Associate, San Francisco
Megan Browdie
Partner, Washington, DC
Annie Froehlich
Partner, Washington, DC
Kevin King
Partner, Washington, DC
John Sellers
Senior Counsel, Palo Alto
Rubin Waranch
Associate, Colorado
Chu Lee
Paralegal Specialist, San Francisco
Katie Kissner
Quantitative Analyst, San Francisco

Related Practices & Industries

Emerging Companies
Artificial Intelligence
Antitrust and Competition
Debt Finance

Harvey Announces $300 Million Series E

Harvey Announces $300 Million Series E

June 24, 2025

Cooley advised Harvey, a domain-specific artificial intelligence platform for legal and professional services, on its $300 million Series E at a $5 billion valuation.

Read more

Related contacts

Matthew Bartus
Partner, San Francisco
Tara Capsuto
Partner, San Francisco
Christopher Kimball
Partner, Washington, DC
Xander Lee
Partner, Santa Monica
John Paul Oleksiuk
Partner, New York
John Sellers
Senior Counsel, Palo Alto
Sharon Connaughton
Special Counsel, Washington, DC
Rebecca Ross
Special Counsel, Washington, DC
Parker Armsby
Associate, New York
Kayla Blaker
Associate, Colorado
Dennis F. Craig II
Associate, Washington, DC
Millie Heuer
Associate, Seattle
Alice C. Hu
Associate, San Francisco
Carl Min
Associate, San Francisco
Tyler Saavedra-Buckley
Associate, San Francisco
Michael Suyat
Senior Paralegal, San Francisco
Katie Kissner
Quantitative Analyst, San Francisco
Brian Mitchell
Transactional Quantitative Analyst, San Diego

Related Practices & Industries

Artificial Intelligence
Technology
Emerging Companies
Antitrust and Competition
CooleyREG
Tax
CFIUS

Decagon Secures $131 Million Series C

Decagon Secures $131 Million Series C

June 23, 2025

Cooley advised Decagon, an innovator in conversational artificial intelligence agents for customer experience, on its $131 million Series C financing round, pushing its total funding to $231 million.

Related contacts

Josh Seidenfeld
Partner, Palo Alto
Zi Ye
Associate, Palo Alto
Yichen Liu
Associate, Palo Alto
Daniel Y. Lee
Associate, Palo Alto
John Sellers
Senior Counsel, Palo Alto
Mark Windfeld-Hansen
Senior Counsel, Palo Alto
Sharon Connaughton
Special Counsel, Washington, DC
David Dalton
Associate, Santa Monica
Christopher Suhler
Associate, Colorado
Irene Sun
Associate, Palo Alto
Melody Van Horn
Senior Paralegal, Palo Alto
Brian Mitchell
Transactional Quantitative Analyst, San Diego

Related Practices & Industries

Emerging Companies
Artificial Intelligence
Antitrust and Competition
Tax
Cyber/Data/Privacy

Decagon Secures $131 Million Series C

Decagon Secures $131 Million Series C

June 23, 2025

Cooley advised Decagon, an innovator in conversational artificial intelligence agents for customer experience, on its $131 million Series C financing round, pushing its total funding to $231 million.

Read more

Related contacts

Josh Seidenfeld
Partner, Palo Alto
Zi Ye
Associate, Palo Alto
Yichen Liu
Associate, Palo Alto
Daniel Y. Lee
Associate, Palo Alto
John Sellers
Senior Counsel, Palo Alto
Mark Windfeld-Hansen
Senior Counsel, Palo Alto
Sharon Connaughton
Special Counsel, Washington, DC
David Dalton
Associate, Santa Monica
Christopher Suhler
Associate, Colorado
Irene Sun
Associate, Palo Alto
Melody Van Horn
Senior Paralegal, Palo Alto

Related Practices & Industries

Emerging Companies
Artificial Intelligence
Antitrust and Competition
Tax
Cyber/Data/Privacy
View more

Admissions and credentials

California

Rankings and accolades

Northern California Super Lawyer: Business Law


M&A Transactions

involving sales of company clients to Google, Apple, IBM, Intel, Qualcomm, Boston Scientific, Stryker and Spectranetics