Sailesh K. Patel

Partner and IP Litigation Practice Co-Leader
International and Fortune 500 clients know who to turn to when facing complex patent litigation or other intellectual property issues.

Sal Patel co-chairs ArentFox Schiff’s Intellectual Property Litigation practice. Sal is a seasoned trial attorney and has first-chaired more than 10 trials and appeals. He is passionate about implementing creative and scientifically sound arguments for his clients, which have resulted in legal precedent-setting cases.

Sal has served as lead counsel on numerous patent infringement litigation matters, trademark infringement litigation matters, and other commercial disputes.

Sal is effective both in trials and in negotiating favorable settlements for his clients. There are many moving parts in patent litigation, and he 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.

Sal has represented pharmaceutical companies in many cases involving Paragraph IV disputes and counsels clients on biosimilars. He has also represented clients in patent litigation involving wind and solar technology, medical devices, life sciences, food processing, automotive components, and software, among other sectors.

With a background in chemical engineering, he has significant experience in preparing and prosecuting patent applications in a variety of technologies. Sal also has significant experience with patent and trademark proceedings in the U.S. Patent and Trademark Office.

Clients rely on Sal for intellectual property transactions and licensing, including contracts involving patent, trademark, copyright, and computer and technology law.

In addition to his legal practice, Sal chairs the firm’s Diversity, Equity, and Inclusion Committee.

Client Work

Representative Hatch-Waxman Paragraph IV Litigation Matters

  • Pfizer v. Aurobindo (D. Del. 2021) Representing Aurobindo in palbociclib, Ibrance®, ANDA litigation
  • Eagle Pharmaceuticals v. Aurobindo (D. Del. 2020) Representing Aurobindo in bendamustine, Bendeka®, ANDA litigation
  • Allergan v. Akorn (E.D. Tex. 2017) Successfully defended Akorn at trial in the E.D. Texas invalidating Allergan’s patent covering Restasis®, a billion dollar ophthalmic product
  • Allergan v. Aurobindo Pharma (D. Del. 2018) Lead counsel for Aurobindo in linaclotide, Linzess®, ANDA litigation
  • The Medicines Company v. Aurobindo (D.N.J. 2017) Lead counsel for Aurobindo in bivalirudin ANDA litigation
  • Horizon v. Lupin (D.N.J. 2017 and Fed. Cir.) Lead counsel for Lupin in Vimovo® ANDA litigation
  • Mylan Institutional v. Aurobindo (E.D. Tex. 2017 and Fed. Cir.) Lead counsel for Aurobindo in patent litigation involving isosulfan blue
  • Eli Lilly v. Ajanta and Aurobindo (E.D. Va. 2017) Lead counsel for Aurobindo and Ajanta pharmaceuticals in litigation involving tadalafil, Cialis®
  • The Medicines Company v. Aurobindo (D.N.J. 2017) Lead counsel for Aurobindo in bivalirudin, Angiomax®, ANDA litigation
  • Allergan v. Akorn (M.D.N.C. 2016 and Fed. Cir.) Lead counsel for Akorn on bimatoprost, Latisse® and Lumigan®, ANDA litigation
  • Depomed v. Alkem (D.N.J. 2016 and Fed. Cir.) Represented Alkem in tapentadol, Nucynta®, ANDA litigation
  • Pfizer v. Fresenius Kabi (D. Del. 2016) Represented FK in tigecycline 505(b)(2) trial
  • Otsuka v. Ajanta and Orchid (D.N.J. 2016) Lead counsel for Ajanta and Aurobindo in aripiprazole, Abilify®, ANDA litigation
  • Acorda Therapeutics v. Aurobindo, Accord and Alkem (D. Del. 2016) Representing Aurobindo, Alkem and Accord in dalfampridine, Ampyra®, ANDA litigation
  • Dexcel v. Sun (D.N.J. 2017) Represented Sun Pharmaceuticals in omeprazole delayed release litigation
  • Pfizer v. Aurobindo (D.N.J. 2015) Lead counsel for Aurobindo in linezolid ANDA litigation
  • Janssen v. Aurobindo (D.N.J. 2015) Lead counsel for Aurobindo in galantamine ANDA litigation
  • Forest v. Sun Pharmaceuticals (D.Del. 2014) Lead counsel for Sun Pharmaceuticals Ltd. in ANDA litigation of the Alzheimer drug Namenda®,memantine XR
  • AstraZeneca v. Aurobindo (D. Del. 2016 and Fed. Cir.) Lead counsel for Aurobindo in ANDA litigation of diabetes drug Onglyza® (saxagliptin)
  • Cephalon v. Glenmark (D. Del. 2014) Lead counsel for Glenmark in bendamustine ANDA litigation
  • Teva Women’s Health v. Lupin (D.N.J. 2012 and Fed. Cir.) Lead counsel for Lupin in ANDA litigation for birth control drugs Seasonique and Loseasonique
  • Teva Women’s Health v. Lupin (D.N.J.) Represented Lupin in Seasonale® ANDA litigation
  • Warner-Chilcott v. Lupin (D.N.J.) Represented Lupin in Loestrin and Femcon ANDA litigation
  • Sciele Pharma v. Lupin (D. Del.) Represented Lupin in metformin, Fortamet, ANDA litigation
  • Shire v. Mylan (D. Del.) Represented Mylan in lanthanum carbonate ANDA litigation
  • Abbott Laboratories v. Mylan Inc. (N.D. Ill.) Represented Mylan in lopinavir/ritonavir ANDA litigation
  • AstraZeneca v. Sandoz (D.N.J.) Represented Sandoz in quetiapine ANDA litigation
  • AstraZeneca v. Lupin (D.N.J.) Represented Lupin in esomeprazole ANDA litigation
  • Sepracor v. Lupin (D.N.J.) Represented Lupin in eszopiclone ANDA litigation
  • AstraZeneca v. Lek and Sandoz (S.D.N.Y.) Represented Lek and Sandoz in omeprazole litigation. Obtained a finding of non-infringement opening the U.S. market for a generic version of Prilosec

Representative Non-Pharma Patent Litigation Matters

  • Rosco, Inc. v. Safety Vision (S.D. Tex. 2020) Lead counsel representing Safety Vision in patent litigation involving vehicle mirror/monitor systems
  • Estech v. Houston Wire & Cable (W.D. Tex. 2020) Lead counsel representing Houston Wire & Cable in patent litigation involving VoIP systems
  • MillerCoors v. HCL Technologies (N.D. Ill. 2018) Representing HCL in SAP software implementation dispute
  • Rosco Inc. v. Velvac Inc. (S.D.N.Y 2015) Lead counsel for Velvac in patent litigation involving fender mounted mirror assemblies
  • Kodak v. DR Systems (S.D. Cal. 2009) Represented Kodak in patent litigation involving MRI imaging systems
  • Schreiber Foods v. Saputo Foods (N.D. Ill.) Represented Schreiber in patent litigation involving imitation cheese
  • Continental Can v. Orexo (N.D. Ill.) Represented Continental Can in patent litigation involving oxygen barrier films

Representative Trademark Matters

  • Joseph Legat v. Legat Architects, Inc. (N.D. Ill. 2021) Representing Legat Architects in trademark infringement litigation
  • Purepecha Enterprises Inc. v. El Matador Adobos, et al. (N.D. Ill. 2012) Representing El Matador Adobos in trademark infringement dispute
  • Sal has also handled many inter partes review petitions in the USPTO relating to LED lighting patents, pharmaceuticals, and internet technology.

Boards, Memberships & Certifications

  • 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

Professional Activities

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

Publications, Presentations & Recognitions


  • R&D Using the Metaverse and Digital Twins,Applied Clinical Trials Magazine (Aug. 11, 2022)
  • “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)


  • “Overcoming IP Issues Relating to the Metaverse and Augmented Reality,” 6th World Legal Tech Summit, Luxatia International, Conference (Sept. 8, 2023)

  • “Patenting AI: Navigating National & Regional Differences, Protecting Inventions and Outputs,” Global IP ConfEx Collaborative Roundtable Discussion, Conference (May 24, 2023)

  • “Building a Robust Invention Harvesting Program - is there a Special Sauce?” IP & Secret Sauce - Virtual Round Table Discussion, Webinar (Apr. 28, 2023)
  • “RVIA General Counsel Meeting,” RV Industry Association, Conference (Oct. 5, 2022)
  • “Trends in Hatch-Waxman Litigation,” IPR Connexion, Webinar (Sep. 2, 2021)
  • “Section 112 Considerations on Pharmaceutical Patents and Litigation,” IPR Connexion, Webinar (Sep. 1, 2021)
  • “Diversity in the Legal Profession,” TerraLex 2020 Virtual Global Meeting, Webinar (Nov. 12, 2020)
  • “Inherent Obviousness: A Case Study on a Less Known but Effective Defense”, 9th Annual Pharma IPR Conference 2020, Mumbai, India (Mar. 4, 2020)
  • “Doctrine of Equivalents: Latest from the Federal Circuit,” Intellectual Property Owners Association, Webinar (Oct. 2, 2019)
  • “Doctrine of Equivalents: Tips for Plaintiffs, Defendants, and Patent Prosecutors,” Intellectual Property Owners Association, Webinar (Jun. 18, 2019)
  • “2018: A Year of Change for Post Issuance Proceedings,” 4th Annual IP Strategy Summit: Chicago, Chicago, Ill. (Jun. 5, 2018)
  • “The On-Sale Bar and its implications in Hatch-Waxman Litigation,” Pharma IPR conference, Mumbai, India (Mar. 2018)
  • “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,”, 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)


  • IAM Patent 1000 – Patent Litigation, Illinois, (2019-2020, 2022)
  • Life Sciences Star – Hatch-Waxman Patent Litigation, LMG Life Sciences (2018-2022)
  • The Best Lawyers in America, Best Lawyers (2019-2024)
  • The Legal 500 United States – Patents: Litigation (2021-2023)
  • Chambers USA – Intellectual Property, Illinois (2021 and 2023-2024)
  • Illinois Super Lawyers, Thomson Reuters (2009, 2012-2014, 2018-2021)
  • IP Star, Managing Intellectual Property (2013-2020)
  • Illinois Leading Lawyer, Law Bulletin’s Illinois Leading Lawyers Network (2013-2021)
  • Nation’s Best – Midwest Region, Lawyers of Color (2019)
  • Peer Reviewed AV® Preeminent™, Martindale-Hubbell (Since 2014)
  • Named to The National Law Journal’s Chicago’s 40 Under 40 Attorneys List for 2013



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