About Mark

Mark Windfeld-Hansen has 20+ years of experience as a tax lawyer. Prior to joining Cooley in 2008, Mark was a shareholder of Heller Ehrman and member of its Venture Law Group. Before its merger with Heller Ehrman, he was a director of Venture Law Group and head of its tax group. Prior to joining VLG, he was a partner and co-chairman of Morrison & Foerster's tax department.

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Experience

Datadog Acquires Eppo

Datadog Acquires Eppo

May 7, 2025

Cooley advised Datadog (Nasdaq: DDOG), a monitoring and security platform for cloud applications, on its acquisition of Eppo, a feature flagging and experimentation platform that will tightly integrate with Datadog’s existing product analytics suite.

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Related contacts

Izzy Lubarsky
Partner, New York
Grigor Lynch
Associate, Colorado
Brittany Sanok
Associate, New York
Eileen Marshall
Partner, Washington, DC
Austin Holt
Partner, Santa Monica
Barbara Mirza
Partner, Santa Monica
Len Jacoby
Partner, New York
Ross Eberly
Partner, Santa Monica
Kristen Mathews
Partner, New York
Megan Browdie
Partner, Washington, DC
Brad Goldberg
Partner, New York
Stella Sarma
Partner, Brussels
Leo Spicer-Phelps
Partner, London
Mark Windfeld-Hansen
Senior Counsel, Palo Alto
Stacey A. Bradford
Special Counsel, Washington, DC
Julia R. Brinton
Special Counsel, Washington, DC
Dillon Martinson
Special Counsel, Washington, DC
Karen Tsai
Special Counsel, Washington, DC
Ryan Bowers
Associate, Washington, DC
David Dalton
Associate, Santa Monica
Cristina DeBiase
Associate, Boston
Megan Drill
Associate, San Diego
Joshua Elefant
Associate, Palo Alto
Nathaniel Hearn Jr.
Associate, Chicago
Allison Kutner
Associate, New York
Edward McLaughlin
Associate, New York
Anisha Mohin
Associate, New York
Juan Nascimbene
Associate, London
Liz Paisner
Associate, New York
Shelby Saunders
Associate, New York
Patricia Myers
Paralegal Specialist, Colorado
Brian Mitchell
Transactional Quantitative Analyst, San Diego

Related Practices & Industries

Mergers and Acquisitions
Technology Transactions
Cloud Solutions
Tax
Compensation and Benefits
Labor and Employment
Cyber/Data/Privacy
Antitrust and Competition
CFIUS

Logik.ai Announces Acquisition by ServiceNow

Logik.ai Announces Acquisition by ServiceNow

April 3, 2025

Cooley advised Logik.ai, an industry leader offering a modern, artificial intelligence (AI)-powered, composable configure, price and quote solution, on its acquisition by ServiceNow (NYSE: NOW), the AI platform for business transformation.

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Related contacts

Sepideh Mousakhani
Partner, Palo Alto
Jon Gavenman
Partner, Palo Alto
Sangitha Palaniappa
Associate, Palo Alto
Megan Browdie
Partner, Washington, DC
Caitlin Courtney
Partner, Palo Alto
Ross Eberly
Partner, Santa Monica
Stella Sarma
Partner, Brussels
Timothy Shapiro
Partner, Palo Alto
Steve Tonsfeldt
Partner, Palo Alto
Mark Windfeld-Hansen
Senior Counsel, Palo Alto
Bryan Berman
Special Counsel, Colorado
Stacey A. Bradford
Special Counsel, Washington, DC
Sharon Connaughton
Special Counsel, Washington, DC
Andrew Epstein
Special Counsel, Seattle
Kristin O'Hanlon
Special Counsel, San Francisco
Karen Tsai
Special Counsel, Washington, DC
Tamara Chin Loy
Associate, Washington, DC
Joshua Elefant
Associate, Palo Alto
Jessica Li
Associate, Palo Alto
Yichen Liu
Associate, Palo Alto
Michael Pelle
Associate, New York
Breanna Qin
Associate, Palo Alto
María Álvarez Requejo Heredero
Associate, Brussels
Erica Russell
Associate, San Francisco
Kealan Santistevan
Associate, Palo Alto
Megan Stallworth
Associate, Palo Alto
Christopher Suhler
Associate, Colorado
Mickeala Tu
Associate, Palo Alto
Chris Rhem
Paralegal Specialist, San Francisco
Katie Kissner
Quantitative Analyst, San Francisco
Brian Mitchell
Transactional Quantitative Analyst, San Diego

Related Practices & Industries

Mergers and Acquisitions
Emerging Companies
Technology Transactions
Technology
Tax
Compensation and Benefits
Antitrust and Competition
Labor and Employment
Commercial Litigation
Cyber/Data/Privacy
CFIUS
Debt Finance

Cerberus Announces Landmark Investment in Aquatech

Cerberus Announces Landmark Investment in Aquatech

April 3, 2025

Cooley advised Cerberus Capital Management, a global leader in alternative investing with approximately $65 billion in assets across complementary credit, real estate and private equity strategies, on its growth investment in Aquatech, a global leader in water technology and services for industrial and infrastructure markets.

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Related contacts

Garland “Sonny” W. Allison
Partner, Colorado
Amelia Runyan Davis
Partner, Colorado
Timothy Shapiro
Partner, Palo Alto
Mark Windfeld-Hansen
Senior Counsel, Palo Alto
Zachary Sonenshine
Associate, New York
Morgan Baker
Associate, Washington, DC
Feroz Khalidi
Associate, Colorado
Matthew Bartus
Partner, San Francisco
Adam Fleisher
Partner, Washington, DC
David Fletcher
Partner, Washington, DC
Steve Flores
Partner, Chicago
Annie Froehlich
Partner, Washington, DC
Todd Gluth
Partner, San Diego
Len Jacoby
Partner, New York
Christopher Kimball
Partner, Washington, DC
Kevin King
Partner, Washington, DC
John Lavoie
Partner in Charge – Reston, Reston
Carly Mitchell
Partner, Washington, DC
John Paul Oleksiuk
Partner, New York
Aaron Pomeroy
Partner, Colorado
Stacey Song
Partner, New York
Michael Tollini
Partner, Washington, DC
Scott Weston
Partner, Boston
Sharon Connaughton
Special Counsel, Washington, DC
Peter Crain
Special Counsel, Reston
Reid Hooper
Special Counsel, Washington, DC
Dillon Martinson
Special Counsel, Washington, DC
Rebecca Ross
Special Counsel, Washington, DC
Grant Schweikert
Special Counsel, Washington, DC
Julie Wicklund
Special Counsel, Palo Alto
Alanna B Zuchelli
Special Counsel, Reston
Meredith Ashlock
Associate, Colorado
Nicholas Balenger
Associate, Reston
Jasmine A. Banks
Associate, Washington, DC
Umer Chaudhry
Associate, Washington, DC
Susan Choy
Associate, New York
Sharon Davidov
Associate, New York
Megan Drill
Associate, San Diego
Jeremy M. Exelbert
Associate, New York
Jimmy Gilligan
Associate, Boston
Michael Gladstone
Associate, New York
Virat Gupta
Associate, Washington, DC
Dr. Aeraj ul Haque
Associate, Chicago
Bomin Kim
Associate, New York
Allison Kutner
Associate, New York
Xueqing Li
Associate, San Francisco
Arthi Naini
Associate, New York
Sarah Oliai
Associate, Washington, DC
Shelby Saunders
Associate, New York
Leanne Andrepont
Senior Trademark Paralegal
Megan Boss
Senior Paralegal , Boston
Patricia Myers
Paralegal Specialist, Colorado
Jill Simon
Senior Paralegal, New York
Luke Sande
Patent Agent, Boston

Related Practices & Industries

Private Equity
Venture Capital
Technology Transactions
Mergers and Acquisitions
Technology
Climate Tech
ESG and Sustainability Advisory
CFIUS
Government Contracts
Tax
Real Estate
Debt Finance
Patent Counseling and Prosecution
Labor and Employment
Compensation and Benefits
Capital Markets
Trademark, Copyright and Advertising
CooleyREG
Fund Formation

SKIMS Acquires SKKN by Kim From Kim Kardashian and Coty

SKIMS Acquires SKKN by Kim From Kim Kardashian and Coty

March 21, 2025

Cooley advised Kim Kardashian, an American media personality, socialite and businesswoman, on SKIMS’ acquisition of SKKN by Kim, a beauty, skincare, and fragrance brand she founded, including the 20% stake held by Coty.

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Related contacts

Matt Hallinan
Partner, Santa Monica
Dave Young
Partner, Santa Monica
Julia Kim
Special Counsel, New York
Kyle Hess
Associate, New York
Katie Benvenuti
Associate, New York
Mark Cikowski
Associate, Santa Monica
Adam Chase
Partner, Washington, DC
Kimberly Nguyen
Special Counsel, Reston
Liz Paisner
Associate, New York
Matthew Caplan
Partner, San Francisco
Stephanie Gentile
Partner, New York
Mark Windfeld-Hansen
Senior Counsel, Palo Alto
Calvin Lee
Associate, New York
John Paul Oleksiuk
Partner, New York
Ross Eberly
Partner, Santa Monica
Austin Holt
Partner, Santa Monica
Bram G. Couvreur
Partner, Santa Monica
Michael Klein
Partner, New York
Michael Neumeister
Partner, Los Angeles
Robert Eisenbach
Of Counsel, San Francisco
Jessica Girone
Associate, Santa Monica

Related Practices & Industries

Fashion, Apparel and Beauty
Retail and Consumer Products
Emerging Companies
Mergers and Acquisitions
Tax
Technology Transactions
Trademark, Copyright and Advertising
Labor and Employment
Compensation and Benefits
Business Restructuring

Boston Celtics Announce $6.1 Billion Sale to Group Led by William Chisholm

Boston Celtics Announce $6.1 Billion Sale to Group Led by William Chisholm

March 20, 2025

Cooley advised the Boston Celtics and the Grousbeck family – the majority stakeholders of Boston Basketball Partners, which owns the American professional basketball team – in connection with their agreement to sell the Celtics to an investor group led by William Chisholm.

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Related contacts

Matthew Hemington
Partner, Palo Alto
Steve Tonsfeldt
Partner, Palo Alto
David Silverman
Partner, New York
Gaël Y. Hagan
Special Counsel , Colorado
Alanna Anderson
Associate, Palo Alto
Ryan Fitzgerald
Associate, Palo Alto
Mark Windfeld-Hansen
Senior Counsel, Palo Alto
Todd Gluth
Partner, San Diego
Patrick Sharma
Associate, Santa Monica
Megan Browdie
Partner, Washington, DC
Rubin Waranch
Associate, Colorado
Michael McMahon
Partner, Boston
Rishab Kumar
Partner, Palo Alto
Eric Jensen
Senior Counsel, Palo Alto
Mark Tanoury
Senior Partner, Palo Alto
Rachel Thorn
Of counsel, New York

Related Practices & Industries

Sports+
Mergers and Acquisitions
Private Equity
Tax
Antitrust and Competition
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Admissions and credentials

California

Rankings and accolades

Best Lawyers in America: Tax Law

Legal 500 US: Domestic Tax (2015)

PATH Act Gives Tax Benefits to Emerging Growth Companies and Investors

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