Generic pharmaceutical manufacturers know who to turn to when facing complex Hatch-Waxman patent litigation. As co-leader of Schiff Hardin’s Intellectual Property Group, Sailesh K. Patel also co-chairs the firm’s Pharmaceuticals and Biologics Patent Litigation Team and is a seasoned trial attorney. He is passionate about implementing creative and scientifically sound arguments for his clients, which has resulted in legal precedent-setting cases.

Sailesh has served as lead counsel on numerous patent infringement litigation matters. With a background in chemical and biomedical engineering, he is familiar with the language of the pharmaceutical industry. Defense against patent infringement requires subject matter experts; Sailesh is skilled at aligning the best experts to successfully defend his clients’ interests.

Sailesh is effective both in trials and in negotiating favorable settlements for his clients. There are many moving parts in patent litigation, and Sailesh is skilled at coordinating multiple parties, experts and arguments into coherent and persuasive cases. In cases where there are multiple defendants, he represents his clients in a way that makes them stand out from the rest, leading to more favorable results. He also assists companies in Paragraph IV and Biosimilars design strategies, helping his clients protect their scientific discoveries.

He has significant experience in preparing and prosecuting patent applications in a variety of technologies beyond pharmaceuticals and biologics. Sailesh has represented clients in cases involving wind and solar technology, food processing, automotive components and software, among other industries.

Previous Experience

Prior to joining Schiff Hardin, Mr. Patel was an associate for a prominent IP law firm.

  • Experience

    • Sailesh is presently defending Glenmark Generics against a patent infringement from Cephalon, Inc., a subsidiary of Teva Pharmaceuticals, in regard to the generic version of Treanda® (bendamustine). Glenmark is also in the process of applying for approval from the FDA to market the generic of the leukemia drug in the U.S.
    • He is also defending Sun Pharmaceuticals Ltd. in a patent infringement lawsuit filed by Forest Laboratories et. al. over the generic extended release version of the Alzheimer drug Namenda® (memantine XR).
    • He is also defending Aurobindo Pharma Limited in a patent infringement lawsuit filed by AstraZeneca over the generic version of diabetes drug Onglyza® (saxagliptin).
    • Sailesh led a team in successfully defending Lupin Ltd. from a patent infringement lawsuit by Teva Women’s Health, Inc. over the birth control drugs Seasonique and Loseasonique. He was able to prove using clear scientific evidence that the patents covering Seasonique and LoSeasonique should be invalidated, ending a monopoly on a $100 million drug more than six years before the patent was set to expire.
    • Sailesh was part of the legal team that successfully defended Lek Pharmaceuticals d.d. from a patent infringement lawsuit by Astra Zeneca AB over the $6 billion drug Prilosec.  The Schiff Hardin team won at trial opening the U.S. market for the generic of the drug.  
    • Sailesh has represented generic pharmaceutical manufacturers such as Aurobindo Ltd., Lupin Ltd., Sandoz, Inc., Akorn Inc. and Mylan Inc. in multiple Hatch-Waxman patent litigation cases.
    • He has also litigated patent cases in several other areas of technology, including electronic imaging, lasers, medical devices, polymer films and food technology.
  • Credentials


    • Boston College Law School, J.D., 1999
    • Northwestern University, B.S., Chemical Engineering, 1996

    Bar Admissions

    • Illinois
    • U.S. Court of Appeals for the Federal Circuit
    • U.S. District Court for the Northern District of Illinois
    • U.S. District Court for the Eastern District of Michigan
    • U.S. Patent and Trademark Office

      Professional Memberships

      • American Bar Association
      • Asian American Bar Association of Chicago, Honorary Board Member
      • Indian-American Bar Association of Chicago, Advisory Council, Past President
      • North American South Asian Bar Association, Former Board of Directors, Intellectual Property Section, Former Chair
      • Intellectual Property Law Association of Chicago, Past Board of Managers
      • The Richard Linn American Inn of Court, Barrister
      • The Economic Club of Chicago

      Teaching Appointments

      • Adjunct Professor, Pharmaceutical Patent Law, Chicago-Kent College of Law
    • Insights


      A View from the Bench: The Federal Judges Speak on Paragraph IV Litigation

      Paragraph IV Disputes Master Symposium – ACI’s Hatch-Waxman Series

      Chicago, Ill.
      News Release

      Schiff Hardin Announces New Diversity Committee Leadership

      Co-Chairs Sailesh K. Patel and Christine A. McGuinness to Focus on Promoting Inclusion, Retention, and Sponsorships


      Supreme Court Delivers Big Patent-Dance-Limiting Win for Biosimilars

      Earlier this week, the U.S. Supreme Court unanimously held, in its first case interpreting the Biologics Price Competition and Innovation Act of 2009, Sandoz Inc. v. Amgen Inc.

      News Release

      Schiff Hardin Recognized as a Top Hatch-Waxman Defense Firm

      Schiff Hardin LLP has been recognized as one of the top law firms defending Abbreviated New Drug Application (ANDA) litigation in the 2017 Hatch-Waxman/ANDA Litigation Report compiled by legal data analytics firm Lex Machina.

      News Release

      Schiff Hardin Expands Global Generic Pharmaceuticals Practice With Addition of Kevin M. Nelson in Chicago

      Schiff Hardin LLP today announced the addition of Kevin M. Nelson as a partner in its rapidly growing Intellectual Property Group.

      News Release

      99 Schiff Hardin Attorneys Named to 2017 Leading Lawyers List

      Ninety-nine Schiff Hardin lawyers have been named to the 2017 Leading Lawyers list for Illinois and Michigan.

      Other Publications

      • “The Supreme Court's Mayo v. Prometheus Decision: The Implications for Biotechnology,” (co-author) The National Law Review (Mar. 23, 2012)
      • “There Is No Orange Book: The Coming Wave of Biological Therapeutics,” (co-author) Oxford University Journal of Intellectual Property Law & Practice (2011)
      • “Inequitable Conduct: Therasense En Banc,” SpicyIP Blog, (India) (Mar. 27, 2011)
      • “Northern Ill.’s New Local Patent Rules,” Law360 (Nov. 6, 2009)
      • “Federal Circuit Review of Markman Issues (2002),” Litigation Committee, Intellectual Property Law Association of Chicago (IPLAC) (Dec. 2003)
      • “Federal Circuit Review of Markman Issues (2001),” Litigation Committee, Intellectual Property Law Association of Chicago (IPLAC) (Dec. 2002)

      Speeches & Presentations

      Sailesh is a regular presenter and faculty member on intellectual property issues. Recent presentations include:

      • “A View from the Bench: The Federal Judges Speak on Paragraph IV Litigation,” (moderator) Paragraph IV Disputes Master Symposium – ACI’s Hatch-Waxman Series, Chicago, Ill. (Oct. 3, 2017)
      • “The State of the Asian American Attorney in Chicago Law Firms,” (panelist) The Chicago Committee, Chicago, Ill. (Jun. 3, 2015)
      • “Takeaways from High-Profile Biosimilar Court Cases,” Business of Biosimilars Conference, Boston, Mass. (Oct. 21, 2014)
      • “Perils of the Safe Harbor: Understanding How the Resetting of the Boundaries of 271(e)(1) in the Aftermath of Classen and Momenta Is Impacting Paragraph IV Litigation Strategies,” American Conference Institute, New York, N.Y. (Apr. 29, 2014)
      • “Cost-Effective Litigation Management Strategies for Paragraph IV Litigation,” Pharma IP and Regulatory Conference, Mumbai, India (Feb. 26, 2014)
      • “Formulating Assertions and Defenses in View of New Substantive and Procedural Developments in the Federal Courts and PTO,” Paragraph IV Disputes Master Symposium, American Conference Institute, Chicago, Ill. (Oct. 3, 2013)
      • “Freedom to Operate Issues and Patent Litigation Considerations for Biosimilars,” Second International Conference on Biowaivers and Biosimilars, Raleigh, N.C. (Sep. 23, 2013)
      • “Breaking Developments in Hatch-Waxman Litigation: Paragraph IV Disputes and Beyond,” Legal and Regulatory Summit on Generic Drugs, New York, N.Y. (Jul. 17, 2013)
      • “Antitrust Concerns in Settlement of Paragraph IV Litigation,” Pharma IP and Regulatory Conference, Mumbai, India (Apr. 10, 2013)
      • “Evaluating the Patentability Standards in the Pharmaceutical Industry to Mitigate the Risks Involved in Product Launches in Analyzing Freedom-to-Operate Issues,” Pharma IPR Conference, Mumbai, India (Feb. 1, 2012)
      • “A Glimpse of the Future – US Biosimilars Litigation Considerations,” Biopractice.com webinar (Dec. 15, 2011)
      • “Alleging and Defending Against Inequitable Conduct in a Paragraph IV Case: Legal and Ethical Considerations,” Paragraph IV Disputes, American Conference Institute, New York, NY (May 4, 2011)
      • “IP Overview for Drugs and Biologics: Hatch-Waxman, BPCIA, Trade Dress, and More,” Paragraph IV Disputes, American Conference Institute, New York, NY (May 2, 2011)
      • “The Scientist: Discussing the ‘Invention’ History With an Eye Towards Distinguishing the Innovative Nature of the Generic Product and Proving Invalidity,” Paragraph IV On Trial, American Conference Institute, New York, NY (Nov. 13, 2009)

    Product Liability and Mass Torts Blog

    FDA Issues Final Guidance on Biosimilars

    Shortly after approving the first biosimilar under the abbreviated approval pathway created by the Biologics Price Competition and Innovation Act of 2009 (“BPCIA”), the FDA has recently issued 3 final guidances regarding biosimilars. Biological products, or “biologics,” are pharmaceutical products created from biological sources. Unlike chemically synthesized pharmaceuticals, biologics are isolated from natural sources, and... Continue Reading