Kathy O'Neill

Partner
Full contact info

I focus on antitrust and competition law, and I advise our clients on all aspects of government merger review, antitrust investigations, litigation and compliance.

Experience

Machinify Announces Acquisition by New Mountain Capital

January 16, 2025

Cooley advised Machinify, a provider of artificial intelligence-powered software transforming healthcare payments, on its definitive agreement to be acquired by New Mountain Capital.

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Partner, Palo Alto
Garth Angelo Osterman
Partner, San Francisco
Maureen Nagle
Special Counsel, Washington, DC
Nicolas Francis
Associate, San Francisco
Katie Rosati
Associate, Seattle
Mark Windfeld-Hansen
Senior Counsel, Palo Alto
David Dalton
Associate, Santa Monica
Steve Flores
Partner, Chicago
Kathy O'Neill
Partner, Washington, DC
Amanda Griggs
Associate, New York
Alexis Finkelberg Bortniker
Partner, San Diego
Ross Eberly
Partner, Santa Monica
Charles Haley
Partner, Palo Alto
Ryan Montgomery
Partner, Boston
Jonathan Rivinus
Partner, Colorado
Mark Medearis
Senior Counsel, Palo Alto
Sharon Connaughton
Special Counsel, Washington, DC
Alexander Ellebracht
Associate, Palo Alto
Josh Himmelstern
Associate, San Diego
Jessica Li
Associate, Palo Alto
Alison L. Tong
Associate, San Francisco
Novak Topalovic
Associate, San Diego
Rubin Waranch
Associate, Colorado
Raquel Zepeda
Associate, San Francisco
Zheng Zhou
Associate, Palo Alto
Patricia Myers
Paralegal Specialist, Colorado
Melanie Yuvienco
Paralegal Specialist, Palo Alto
Brian Mitchell
Transactional Quantitative Analyst, San Diego

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Laekna Announces Clinical Collaboration With Lilly

November 26, 2024

Cooley advised Laekna (HKSE: 2105.HK), global biotech company focused on novel drug development for metabolic and cancer diseases, on its clinical collaboration with Eli Lilly and Company to accelerate the development of LAE102, a novel ActRIIA mAb as a treatment for obesity.

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Yiming Liu
Partner in Charge – Shanghai, Shanghai
Bin Wang
Special Counsel, Palo Alto
Zack Gong
Associate, Shanghai
Kathy O'Neill
Partner, Washington, DC
David Burns
Special Counsel, Washington, DC
Tonny Yu
Associate, Hong Kong
Zhijing Yu
Associate, Singapore

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Kpler Announces $241 Million Acquisition of Spire’s Maritime Business

November 13, 2024

Cooley advised Kpler, a fast-growing data and analytics firm on a mission to build one platform for global trade intelligence, on its acquisition of Spire Global’s maritime business for approximately $241 million.

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Ben Shribman
Partner, London
Rita Sobral
Special Counsel, London
Leo Spicer-Phelps
Partner, London
Louise Burt
Associate, London
Marzia Di Candido
Associate, London
Christine Graham
Special Counsel, London
Caroline Hobson
Partner, London
Mo Swart
Associate, London
Natasha Kaye
Partner, London
Eerik Kukebal
Associate, London
Jeffrey J. Tolin
Partner, New York
Chris Coulter
Partner, London
David Fletcher
Partner, Washington, DC
Christopher Kimball
Partner, Washington, DC
Kathy O'Neill
Partner, Washington, DC
Chris Stack
Partner, London
Amy Collins
Special Counsel, London
Sharon Connaughton
Special Counsel, Washington, DC
Rebecca Ross
Special Counsel, Washington, DC
Stella Sarma
Special Counsel, Brussels
Cristina DeBiase
Associate, Boston
Liza Hadley
Associate, Boston
Chris Lynn
Associate, London
Daniel Millard
Associate, London
Rubin Waranch
Associate, Colorado

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Printify Announces Merger With Printful

November 11, 2024

Cooley advised Printify, a technology platform headquartered in Latvia that makes it possible for anyone, anywhere, to sell customized products with zero upfront investment, on its merger with Printful, a Latvia-based technology company that helps ecommerce sellers of all sizes use production-on-demand and other fulfillment solutions to turn their ideas into brands and products.

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Nick Davis
Partner in Charge – Seattle, Seattle
John Robertson
Partner, Seattle
Caitlin Breitenbruck
Associate, Seattle
Phoebe Huang
Associate, Seattle
Katie Rosati
Associate, Seattle
Tracy Rubin
Partner, Palo Alto
Michael Bergmann
Partner, Washington, DC
Paula Holland
Partner, London
Kathy O'Neill
Partner, Washington, DC
Jonathan Rivinus
Partner, Colorado
Megan Browdie
Partner, Washington, DC
Ross Eberly
Partner, Santa Monica
Andrew Epstein
Special Counsel, Seattle
Sharon Connaughton
Special Counsel, Washington, DC
Karen Tsai
Special Counsel, Washington, DC
Stella Sarma
Special Counsel, Brussels
Zheng Zhou
Associate, Palo Alto
Rebecca Siegel
Associate, San Francisco
Queenie Chen
Associate, Palo Alto
Lucy Bauer
Associate, Seattle
Raquel Zepeda
Associate, San Francisco
Rick Jantz
Associate, Santa Monica
Leo Spicer-Phelps
Partner, London
Nicollette R. Kirby
Associate, Washington, DC
Breanna Qin
Associate, Palo Alto
Gary Warren Hunt III
Associate, Washington, DC

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Avid Bioservices Announces $1.1 Billion Acquisition by GHO Capital Partners and Ampersand Capital Partners

November 6, 2024

Cooley advised Avid Bioservices (Nasdaq: CDMO), a dedicated biologics contract development and manufacturing organization (CDMO) working to improve patient lives by providing high quality development and manufacturing services to biotechnology and pharmaceutical companies, on its definitive merger agreement to be acquired by funds managed by GHO Capital Partners and Ampersand Capital Partners in an all-cash transaction valued at approximately $1.1 billion.

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Bill Sorabella
Partner, New York
Matthew D. Silverman
Special Counsel, Santa Monica
Natalie D. Vernon
Associate, Colorado
Sarah Buchik
Associate, New York
Patrick Reed
Associate, Palo Alto
Alexis Johnson
Associate, Boston
David Silverman
Partner, New York
Baasit Bhutta
Associate, Colorado
Barbara Mirza
Partner, Santa Monica
Austin Holt
Partner, Santa Monica
Tony P. Guan
Associate, Santa Monica
Howard Morse
Partner, Washington, DC
Kathy O'Neill
Partner, Washington, DC
Julia R. Brinton
Special Counsel, Washington, DC
Phil Mitchell
Partner, New York
Natasha Leskovsek
Of Counsel, Washington, DC
Wyatt Kernell
Associate, Colorado
Elizabeth Caruso
Associate, New York
Sarah Miller
Associate, New York
Eileen Marshall
Partner, Washington, DC
Todd Gluth
Partner, San Diego
Calvin Lee
Associate, New York
Christophe Beauduin
Partner, New York
Charity Williams
Partner, San Diego
Jameson Davis
Associate, Boston
Koji Fukumura
Partner, San Diego
Peter Adams
Partner, San Diego
Michael Egan
Partner, Washington, DC
Gary Warren Hunt III
Associate, Washington, DC
Ellie Seber
Partner, Santa Monica
Alexandra Leavy
Associate, New York
Timothy Nguyen
Special Counsel, San Francisco
Justin Kisner
Special Counsel, Palo Alto
Christopher Kimball
Partner, Washington, DC
Shelby Saunders
Associate, New York
Ross Eberly
Partner, Santa Monica
Joshua Elefant
Associate, Palo Alto
Alanna B Zuchelli
Special Counsel, Reston
Leanne Andrepont
Senior Trademark Paralegal
Megan Boss
Senior Paralegal , Boston

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Kathy O'Neill is incredibly analytical.

Chambers USA, 2024

Kathy is an outstanding lawyer. She has great judgment.

Chambers USA, 2024

Admissions and credentials

New York

Pennsylvania

District of Columbia

Rankings and accolades

Chambers USA: Antitrust – District of Columbia (2024)

Women@Competition: 40 in their 40s Notable Women Competition Professionals in Europe, the Americas and Africa (2019)

Global Competition Review: Women in Antitrust award (2016)

DOJ Antitrust Division: Assistant Attorney General Award for outstanding contributions to enforcement matters (eight-time winner)