Daniel B. Ravicher, Partner


University of Virginia, J.D.

University of South Florida, B.S.C.E.


Phone: (786) 505-1205


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New York

Supreme Court Of The United States

U.S. Courts of Appeals for the 2nd, 9th, 11th and Federal Circuits

U.S. District Courts for the Middle and Southern Districts of Florida, the Eastern and Southern Districts of New York, and the Eastern and Western (pro hac vice) Districts of Texas

U.S. Patent & Trademark Office (Reg. No. 47,015)


Daniel B. Ravicher represents clients in business and technology related litigation and transactions, which he’s done since the dotcom boom.

Dan’s litigation experience includes representing intellectual property rights holders and accused infringers in cases across the country involving pharmaceuticals, biotechnology, medical devices, semiconductors, telecommunications, software, consumer electronics, and other technologies. He won the 2013 Supreme Court case that held human genes cannot be patented, which is the subject of the 2021 book The Genome Defense by Jorge Contreras. He also successfully protected organic farmers from Monsanto’s patents on genetically modified seed, represented developers of free/open source software in enforcing the General Public License (GPL) and other open source licenses, and defended clients including the NYC Transit Authority from patent trolls.

Outside the courts, Dan has represented both patent holders and challengers in inter partes reviews and other proceedings at the U.S. Patent & Trademark Office in matters relating to biotech, pharmaceutical, software, and electronic technologies. In addition to intellectual property, he has also litigated disputes involving breach of contract, corporate law, Federal and state securities laws, fraud, antitrust, and civil liberties. Dan has litigated in various federal and state courts and administrative proceedings as well as both domestic and international arbitrations.

Dan’s transactional experience includes financing, exit, and technology transactions. He has represented clients in angel, VC, M&A, and IPO transactions, negotiated sales and licenses of intellectual property, and advised on intellectual property infringement, validity, and valuation issues. A registered patent attorney, Dan has also prosecuted patents, trademarks, and copyrights for clients. In addition to being an investor in and advisor to private and public life sciences, information technology, crypto and other companies and projects, he also regularly consults with investment banks, hedge funds, and individual investors on legal issues that may materially affect the value of private and publicly traded companies.

Dan was twice named one of ‘The 50 Most Influential People in IP’ by Managing Intellectual Property and Appellate Lawyer of the Week by the National Law Journal. He appeared as a guest on the PBS NewsHour and has been quoted by the Wall Street Journal, the New York Times, the Financial Times, and countless other publications. He has presented at dozens of conferences and public events on issues relating to technology law, including being invited by Congress twice to be a witness on the topic of patent reform. Dan has also consulted with the United Nations and other international bodies on legal issues impacting access to essential medicines.

Professional History

Prior to Zeisler PLLC, Dan directed the Public Patent Foundation, a non-profit patent reform organization he founded with support from the Rockefeller Foundation, the Nathan Cummings Foundation, the Open Society Foundation, and the Echoing Green Foundation, among others. He was previously associated with Brobeck, Phleger & Harrison LLP, and Patterson Belknap LLP, both in New York. Dan was also a law professor for fifteen years at Benjamin N. Cardozo School of Law and the University of Miami School of Law teaching Patent Law and Startup Law.


Dan is admitted to the U.S. Supreme Court, the U.S. Courts of Appeals for the Federal, 2nd, and 11th Circuits, the U.S. District Courts for the Southern and Eastern Districts of New York and the Southern and Middle Districts of Florida, the States of New York and Florida, and the U.S. Patent and Trademark Office.


Dan received his law degree from the University of Virginia School of Law, where he was the Franklin O’Blechman Scholar of his class, a Mortimer Caplin Public Service Award recipient, and an Editor of the Virginia Journal of Law and Technology.  He received his bachelors degree in materials science magna cum laude with University Honors from the University of South Florida.