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umberg-zipser-llp
  • (949) 679-0052
  • [email protected]
  • ABOUT
    • Firm Overview
    • Selected Honors & Awards
    • Professional Activities & Community Involvement
    • Charitable Support
    • Careers
  • PRACTICE AREAS
    • Commercial Litigation
    • Intellectual Property
    • Lawyer Liability & Legal Ethics
    • Class Actions
    • Government & Regulatory
    • White Collar Investigations & Defense
  • PROFESSIONALS
    • Brent S. Colasurdo
    • Ryan S. Dean
    • Ethan Feng
    • Martin Fessenmaier, Ph.D.
    • Mark A. Finkelstein
    • Scott B. Garner
    • Phillip R. Kaplan
    • Ellen S. Kim
    • Priti Phukan, Ph.D.
    • Carole E. Reagan
    • Todd W. Smith
    • Adina W. Stowell
    • Jason Tejani
    • Mei Tsang
    • Thomas J. Umberg
    • Vikki L. Vander Woude
    • Dean J. Zipser
    • Other
      • Halim Dhanidina
  • NEWS
  • CONTACT
Menu
  • ABOUT
    • Firm Overview
    • Selected Honors & Awards
    • Professional Activities & Community Involvement
    • Charitable Support
    • Careers
  • PRACTICE AREAS
    • Commercial Litigation
    • Intellectual Property
    • Lawyer Liability & Legal Ethics
    • Class Actions
    • Government & Regulatory
    • White Collar Investigations & Defense
  • PROFESSIONALS
    • Brent S. Colasurdo
    • Ryan S. Dean
    • Ethan Feng
    • Martin Fessenmaier, Ph.D.
    • Mark A. Finkelstein
    • Scott B. Garner
    • Phillip R. Kaplan
    • Ellen S. Kim
    • Priti Phukan, Ph.D.
    • Carole E. Reagan
    • Todd W. Smith
    • Adina W. Stowell
    • Jason Tejani
    • Mei Tsang
    • Thomas J. Umberg
    • Vikki L. Vander Woude
    • Dean J. Zipser
    • Other
      • Halim Dhanidina
  • NEWS
  • CONTACT
Exceptional Quality With The Personal Service Of A Boutique
Umberg/Zipser's team of accomplished professionals are consistently recognized as among the very best in their
practice areas.
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Experience

Integrity

Results

2
Best Lawyers 2022
Civic 50 OC
ocba
5
Best Lawyers 2021
SL Badge 2021
best-law-firms-badge-small-2020
super-lawyers-2020
best-law-firms-badge-small-2020
best-law-firms-badge-small-2019
americas-top-100
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Firm Overview

About Us

Umberg/Zipser LLP is a premier business litigation and intellectual property boutique law firm. Drawing on decades of experience in some of the nation’s largest and most prestigious law firms, as well as national and state government service, our lawyers provide exceptional work with the unparalleled personal service of a boutique.  

Our Culture

Umberg/Zipser believes in giving back, both to our community and to our profession. We regularly handle pro bono matters, and our attorneys devote countless hours to supporting — and leading — professional and community organizations. It would be difficult to find another firm in Orange County, regardless of size, that can boast the number of community leaders that exist at Umberg/Zipser.

Why Us?

By combining big-firm experience with small-firm efficiencies, we can handle complex matters for large companies, but we also are nimble enough to represent small companies and entrepreneurs. Our clients come to us because we deliver the highest quality work product together with extraordinary service.

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Practice Areas

We Have the Experience to Handle a Wide Array of Matters

Commercial Litigation
We handle a wide variety of commercial litigation matters, including breach of contract, fraud, unfair competition, and other business torts.
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Intellectual Property
We provide national and international patent and trademark prosecution services, and we litigate matters involving patents, trademarks, copyrights, false advertising, and trade secrets.
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Lawyer Liability & Legal Ethics
Our attorneys have extensive experience defending law firms and lawyers against claims by former clients and third parties.
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Class Actions
We have handled scores of class action cases in state and federal courts involving a wide variety of claims and subject areas.
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Government & Regulatory
We develop effective, practical strategies to address the governmental issues that impact our clients.
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White Collar Investigations & Defense
Our attorneys have deep experience in defending and investigating allegations of white collar criminal conduct.
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Commercial Litigation
We handle a wide variety of commercial litigation matters, including breach of contract, fraud, unfair competition, and other business torts.
LEARN MORE
Intellectual Property
We provide national and international patent and trademark prosecution services, and we litigate matters involving patents, trademarks, copyrights, false advertising, and trade secrets.
LEARN MORE
Lawyer Liability & Legal Ethics
Our attorneys have extensive experience defending law firms and lawyers against claims by former clients and third parties.
LEARN MORE
Class Actions
We have handled scores of class action cases in state and federal courts involving a wide variety of claims and subject areas.
LEARN MORE
Government & Regulatory
We develop effective, practical strategies to address the governmental issues that impact our clients.
LEARN MORE
White Collar Investigations & Defense
Our attorneys have deep experience in defending and investigating allegations of white collar criminal conduct.
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VIEW ALL PRACTICE AREAS

Professionals

We Have Exceptional Attorneys Who Stand Ready to Serve Our Clients

Brent S. Colasurdo

  • (949) 679-0052
  • [email protected]
Brent S. Colasurdo is an associate with Umberg/Zipser where he focuses his practice on complex commercial litigation.
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Ryan S. Dean

  • (949) 679-0052
  • [email protected]
Ryan specializes in global patent and trademark prosecution for clients of all sizes, and focuses primarily in the areas of mechanical and aerospace engineering
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Halim Dhanidina - Partner U/Z

Halim Dhanidina


  • (949) 679-0052

  • [email protected]

The Honorable Halim Dhanidina (Ret.) is a partner at the prestigious criminal defense firm of Werksman Jackson & Quinn LLP in Los Angeles, where he handles challenging and high profile criminal cases. He serves as co-counsel with Umberg/Zipser in a variety of civil matters as the firm’s Senior Trial and Appellate Counsel.


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Ethan Feng

  •  (949) 679-0052
  •  [email protected]

Ethan Feng is an associate at Umberg/Zipser where he focuses his practice in complex commercial litigation, professional liability disputes, and employment litigation.

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Martin Fessenmaier, Ph.D.

  • (949) 679-0052
  • [email protected]
Martin has almost two decades of experience in domestic and International patent prosecution, working in the fields of biochemistry and molecular biology, bioinformatics, medical devices, organic chemistry, and general mechanical arts.
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Mark A. Finkelstein

  • (949) 679-0052
  • [email protected]

Mark Finkelstein is a partner at Umberg/Zipser with more than 25 years of intellectual property and complex litigation experience.


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Scott B. Garner

  • (949) 679-0052

  • [email protected]

Scott B. Garner is a partner at Umberg/Zipser in Irvine, California. He represents clients in complex business litigation matters, with a particular focus on professional liability disputes and ethics counseling.


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Phillip R. Kaplan

Partner

  • (949) 679-0052
  • [email protected]

Phillip R. Kaplan is a recognized leader in the Orange County legal community, and is an accomplished business trial lawyer with a record of handling his client’s most difficult cases. 


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Ellen S. Kim


  • (949) 679-0052
  • [email protected]

Ellen Kim is an Associate at Umberg/Zipser LLP (U/Z) where she focuses her practice in complex commercial litigation.

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Priti Phukan, Ph.D.

  • (949) 679-0052
  • [email protected]
Priti Phukan concentrates her practice on patent and trademark prosecution across various technology industries, including chemistry, life sciences, diagnostics, medical devices, and mechanical engineering.
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Carole E. Reagan

  • (949) 679-0052
  • [email protected]
Carole E. Reagan’s practice focuses on intellectual property and complex commercial litigation. She has successfully represented business clients across a diverse array of industries.
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Todd W. Smith

  • (949) 679-0052
  • [email protected]
Todd Smith’s practice focuses on complex business litigation in state and federal courts representing companies and individuals in partnership disputes, shareholder and derivative litigation, real estate disputes, trade secrets, and unfair competition claims.
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Adina W. Stowell

  • (949) 679-0052
  • [email protected]

Adina Stowell specializes in complex litigation involving corporate, commercial, trade secret, and real estate disputes in both state and federal courts.

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Jason Tejani

  •  [email protected]

Jason Tejani concentrates his practice on patent prosecution and intellectual property (IP) transactional matters. Prior to his legal career, he was a chemist at a global chemical company.


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Mei Tsang

  • (949) 679-0052
  • [email protected]
Mei has an international intellectual property practice focused on helping clients formulate their IP strategy, and shepherding their IP through various business cycles to achieve their business goals worldwide.
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Thomas J. Umberg

  • (949) 679-0052
  • [email protected]
Thomas J. Umberg has extensive trial experience in both federal and state courts and has been selected as a “Best Lawyer” for the prestigious publication “The Best Lawyers in America®” in commercial litigation for 12 consecutive years.
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Vikki L. Vander Woude

  • (949) 679-0052
  • [email protected]
Vikki has a broad and diverse professional background having worked in large and small law firms, as in-house counsel, and as a research attorney for the courts, which gives her a unique perspective and skill set that is of immeasurable benefit to clients.
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Dean Zipser

Dean J. Zipser


  • (949) 679-0052
  • [email protected]

Dean J. Zipser is a recognized leader in the Orange County legal community, having served as President of the Orange County Bar Association (OCBA) along with many other professional leadership positions.


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NEWS and EVENTS

Umberg/Zipser in the Community

Orange County Bar Association (OCBA) Annual Judges’ Night 2022

April 19, 2022

On Thursday, April 7th, the Orange County Bar Association (OCBA) held its annual Judges’ Night. It was a special evening, as the OCBA returned to an in-person event after two years. Hundreds celebrated as the Honorable Judge David O. Carter installed the new OCBA officers and directors, including Umberg/Zipser’s own Mei Tsang as OCBA Secretary. Mei is now in line to become OCBA President

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Thomas J. Umberg Recognized As 2022 Legislator of the Year

April 7, 2022

The California Lawyers Association has recognized California Senator Thomas J. Umberg as the 2022 Legislator of the Year. ” As Chair of the Senate Judiciary Committee, Senator Umberg has taken the lead on passing legislation that is integral to the daily practice of CLA members and that improves the lives of all Californians.” California Lawyers Association President, Jeremy M. Evans, said “CLA is grateful for the ability to work with Senator

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Scott Garner Leads OCBA Charitable Fund Grant Reception

March 25, 2022

The Orange County Bar Association Charitable Fund annual reception held last Wednesday honored a number of nonprofit organizations making a positive impact in OC communities. Scott Garner, Umberg/Zipser Partner, and Past President of the OCBA Charitable Fund, had the privilege of presenting grants to the various local non-profits. The Charitable Fund’s mission is to provide resources to organizations and programs to enhance the system

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Super Lawyers 2022 Selects Seven Umberg/Zipser Attorneys

January 25, 2022

Umberg/Zipser LLP is proud to announce that seven of its partners have been included in the Southern California Super Lawyers list for 2022, a recognition reserved for only five percent of lawyers in California.  In addition, both Dean Zipser and Scott Garner have been recognized this year as a Top 50 Orange County Lawyer, Dean for the fourth consecutive year. The following Umberg/Zipser attorneys have been recognized in the Southern California Super

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Partner Mei Tsang Elected as Secretary of the Orange County Bar Association (OCBA)

January 18, 2022

On Thursday, January 13th, the Orange County Bar Association (OCBA) installed its new officers and directors for the year 2022 in a small ceremony outdoors. We are delighted to now formally congratulate Umberg/Zipser’s own partner, Mei Tsang, on her new role as OCBA Secretary!  In 2025, Mei will become the third U/Z attorney who will have served as OCBA President, following Dean Zipser and

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Umberg/Zipser LLP Announces Attorney Ellen S. Kim has Joined the Firm

December 28, 2021

Umberg/Zipser (U/Z) is delighted to welcome our newest attorney, Ellen S. Kim, to our team! Ellen brings a broad range of successful legal experience, having represented clients in complex commercial litigation matters including business disputes and consumer class actions. Ellen also maintains an active pro bono practice, where she represents survivors of human trafficking and asylum seekers. Prior to joining U/Z, Ellen served as

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CAREERS

Come Join Our Amazing Team

If you are an exceptional attorney who thrives on delivering top-notch client service, and would enjoy practicing law in a small, collegial environment, we invite you to contact us to learn more about how we can support your career growth. Umberg/Zipser is proud of its diversity, and is an equal opportunity employer.

CONTACT US

Umberg Zipser

1920 Main Street, Suite 750 Irvine CA 92614

Contact Us

If you are interested in retaining our services, or you want to learn more about Umberg/Zipser, we look forward to hearing from you.  Please note that merely sending us an email does not create an attorney-client relationship, and anything you send to us will not be confidential or privileged unless we have agreed to represent you. 

  • (949) 679-0052
  • 1920 Main Street, Suite 750, Irvine, CA 92614
  • [email protected]
  • www.umbergzipser.com

Umberg/Zipser is a premier business litigation and intellectual property boutique.  Drawing on decades of experience in some of the nation’s largest and most prestigious law firms, as well as national and state government service, Umberg/Zipser provides clients with unparalleled legal services. 

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  • ABOUT
    • Firm Overview
    • Selected Honors & Awards
    • Professional Activities & Community Involvement
    • Charitable Support
    • Careers
  • PRACTICE AREAS
    • Commercial Litigation
    • Intellectual Property
    • Lawyer Liability & Legal Ethics
    • Class Actions
    • Government & Regulatory
    • White Collar Investigations & Defense
  • PROFESSIONALS
    • Brent S. Colasurdo
    • Ryan S. Dean
    • Ethan Feng
    • Martin Fessenmaier, Ph.D.
    • Mark A. Finkelstein
    • Scott B. Garner
    • Phillip R. Kaplan
    • Ellen S. Kim
    • Priti Phukan, Ph.D.
    • Carole E. Reagan
    • Todd W. Smith
    • Adina W. Stowell
    • Jason Tejani
    • Mei Tsang
    • Thomas J. Umberg
    • Vikki L. Vander Woude
    • Dean J. Zipser
    • Other
      • Halim Dhanidina
  • NEWS
  • CONTACT
Menu
  • ABOUT
    • Firm Overview
    • Selected Honors & Awards
    • Professional Activities & Community Involvement
    • Charitable Support
    • Careers
  • PRACTICE AREAS
    • Commercial Litigation
    • Intellectual Property
    • Lawyer Liability & Legal Ethics
    • Class Actions
    • Government & Regulatory
    • White Collar Investigations & Defense
  • PROFESSIONALS
    • Brent S. Colasurdo
    • Ryan S. Dean
    • Ethan Feng
    • Martin Fessenmaier, Ph.D.
    • Mark A. Finkelstein
    • Scott B. Garner
    • Phillip R. Kaplan
    • Ellen S. Kim
    • Priti Phukan, Ph.D.
    • Carole E. Reagan
    • Todd W. Smith
    • Adina W. Stowell
    • Jason Tejani
    • Mei Tsang
    • Thomas J. Umberg
    • Vikki L. Vander Woude
    • Dean J. Zipser
    • Other
      • Halim Dhanidina
  • NEWS
  • CONTACT

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