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DenisSullivan

He | Him | His

Partner

"My mastery of technology and IP law is informed by my experience as a former licensed electrical engineer, first-chair litigator, and registered patent attorney."

Overview

Biography

Denis heads Barclay Damon’s Intellectual Property Practice Group. After gaining experience and training at an Am Law 5 firm, he brought his practice to Barclay Damon and offers high-caliber legal skills with a focus on cost-effectiveness to better serve his clients’ business needs. Many clients describe Denis as a rare talent who successfully helps them protect, defend, and monetize their innovations.

His national practice includes handling patent infringement disputes in federal district court and patent office proceedings such as inter partes reviews and reexaminations. Denis also adeptly advises clients on strategically managing and optimizing their patent portfolios, both domestically and internationally.

Denis’s years of experience as a licensed professional electrical engineer enable him to deliver high-value intellectual property counsel, strengthened by his ability to grasp complex technical issues across a wide range of industries. As an example, Denis recently successfully represented a mid-sized company sued for patent infringement by a much larger competitor on several high-tech patents in a bet-the-company litigation. With a deep understanding of the technology, Denis developed and executed several key strategic maneuvers, causing the competitor to walk away and drop the lawsuit early in the litigation. 

Denis graduated first in his class with a degree in electrical engineering. While working as an engineer, he attended law school at night and again graduated first in his class.

Denis began his legal career as an associate in the IP Litigation Department of Kirkland & Ellis in New York City before moving his practice to an intellectual property boutique in Central New York, where he served as managing partner.

Bar Associations

  • New York State Bar Association

Selected Memberships & Affiliations

  • American Intellectual Property Law Association
  • Intellectual Property and Innovation American Inn of Court
  • New York State Licensed Professional Engineer
Experience

Representative Experience

  • Served as lead counsel in over 30 IPRs of patents involved in district court litigation.
  • Served as lead counsel in federal circuit appeals of IPR decisions.
  • Served as lead counsel in reexaminations of several patents involved in district court litigation.
  • Served as lead counsel in a patent infringement action involving software patents for electronic shareholder communications.
  • Served as trial counsel in an ITC proceeding involving patents for coaxial-cable connectors. Obtained two general-exclusion orders and one limited-exclusion order.
  • Served as trial counsel in a declaratory judgment action involving patents for chemical de-icers.
  • Served as lead patent counsel in a district court appeal of the USPTO interference proceeding. Obtained a summary judgment reversing the patent office to preserve the validity of the patent.
  • Prepares and prosecutes patent and trademark applications and appeals for domestic and foreign clients, including Fortune 100 clients.
  • Provides counseling and legal opinions concerning the validity and infringement of patents and trademarks.
  • Provides patent counseling to a leading provider of instrumentation, sensors, and advanced process control software in the semiconductor manufacturing industry.

Prior Experience

  • Marjama Muldoon Blasiak & Sullivan LLP, Partner
  • Kirkland & Ellis LLP, Associate
  • Port Authority of New York and New Jersey, Electrical Engineer and Project Manager

Selected Community Activities

  • Youth Sports Coach
Knowledge

Selected Speaking Engagements

  • Practicing Law Institute’s 11th Annual Patent Law Institute, “The Patent Trial and Appeal Board Turns Five”
  • IP Counsel Exchange, “PTAB Litigation Crash Course: A Litigator’s Guide to Obtaining Successful Results at the PTAB”
  • Rochester Intellectual Property Law Association, “Escaping From Wonderland: An Analysis of Decisions Where Patent Claims Have Survived Section 101 Challenges Under Alice Corp. v. CLS Bank
  • Practicing Law Institute’s Ninth Annual Patent Law Institute, "Inter Partes Review and Post-Grant Review: Interplay of PTAB/District Court Litigation"

Selected Media

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