David O. Klein

Managing Partner


B.A. 1989, Colgate University
J.D. 1992, Hofstra University School of Law
L.L.M. 1994, Pace University Law School, Environmental Law

David is admitted to practice in New York and New Jersey, before the US District Court, Southern and Eastern District of New York, and the US District Court in New Jersey.

Martindale-Hubbell AV Rating


David Klein is one of the most recognized attorneys in the telemarketing, technology, Internet marketing, sweepstakes and telecommunications fields. Skilled at counseling clients on a broad range of technology-related matters, David Klein has substantial experience in negotiating and drafting complex licensing, marketing, NFT and Internet agreements. He has an in-depth understanding of Internet, telemarketing and new media law and is established as a leader in structuring and implementing major technology agreements.

Well-versed in sweepstakes law, NFT law, gaming law, and laws pertaining to fantasy sports and other promotions, David helps steer clients through the ever-evolving legal landscape associated with their new media ventures (ensuring that all creative material complies with applicable law, drafting new media marketing agreements and drafting contest rules for sweepstakes and other promotions).

Areas of Focus

  • E-commerce, Internet Marketing, Social Media, E-mail Marketing and Advertising Law
  • Telemarketing Law
  • NFT Law
  • Promotions Law and Sweepstakes Law
  • Gaming Law and Fantasy Sports Law
  • Mobile Marketing Law
  • Privacy and Data Security Law
  • Telecommunications Law
  • Copyright and Trademark Law
  • Domain Name Controversies
  • Software Licensing
  • Trade Secret Misappropriation Claims

Professional Activities

David represents clients before the New York State trial and appellate courts, federal courts, the Federal Communications Commission, the Federal Trade Commission, State Public Service Commissions, state attorneys general, as well as before the American Arbitration Association and other arbitral tribunals. He is an active member of the Fantasy Sports Trade Association (FSTA).

David speaks and writes extensively on intellectual property, telemarketing and Internet marketing, promotions, and technology issues.  His legal analysis has been featured on Fox News, the Wall Street JournalYahoo! Finance, the Washington PostBuzzFeedBloomberg Business and other popular news outlets.  David has authored numerous articles for AdWeek, Law360Justia, PHONE+, Revenue, Feedfront, Revenue Performance, Website Magazine, Vice and other publications.


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