William Zimmerman

Partner

Washington DC

202-640-6400

bill.zimmerman@knobbe.com

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Overview

Experience

Recognition

Resources

Having served as lead counsel in over 100 pharmaceutical litigations, including cases involving “blockbuster” drugs like Lipitor and Nexium, William R. Zimmerman is widely recognized as one of the nation’s premier life science litigators. As co-chair of both the firm’s Hatch-Waxman and Life Sciences Practice Groups, Bill oversees a diverse team of attorneys who have collectively litigated over 200 complex cases involving pharmaceutical products.

Recognized as the “Hatch-Waxman Litigator of the Year,” Bill Zimmerman is well-versed in the Abbreviated New Drug Application process and the complexities Hatch-Waxman litigation. He has been widely acknowledged for his expertise in pharmaceutical matters, being repeatedly named one of “The World’s Leading Patent Professionals” by IAM, a “Life Science Star” by LMG, an “IP Star” by Managing IP, and a “Washington D.C. Super Lawyer” by Super Lawyer’s Magazine. He was previously named one of the top fifty intellectual property lawyers under the age of forty by IP Law & Business magazine.

Bill is the founding managing partner of the firm’s Washington, D.C. office. Before joining the firm, he served as a law clerk to the Honorable Alvin A. Schall, Circuit Judge of the United States Court of Appeals for the Federal Circuit.

Education

Harvard Law School (J.D., 1997), Member - Harvard Journal of Law & Technology, Member - Harvard Environmental Law Review, cum laude

University of Notre Dame (B.S. Chemical Engineering, 1994), Tau Beta Pi - Engineering Honor Society, summa cum laude

Harvard Law School

University of Notre Dame

State Bar of California

District of Columbia Bar

Supreme Court of the United States

U.S. Court of Appeals for the Federal Circuit

Biosimilars

Biotechnology

Chemical

Medical Devices & Procedures

Pharmaceuticals

Practice Areas

IP Strategy

Opinions & Counseling

Appellate Litigation

Hatch-Waxman Litigation

Medical Device Litigation

PTAB IPR & Post-Grant Proceedings

Patent Office Litigation

Bristol-Myers Squibb Co. v. Lupin Inc., Case No. 3:20-cv-07810 (2021)

Represented Lupin in Hatch-Waxman litigation in the District of New Jersey concerning patents related to dasatinib (the active ingredient in BMS’s Sprycel® product). Achieved a favorable disposition for the client prior to claim construction briefing.

Illumina, Inc. v. The Trustees of Columbia University, Case Nos. IPR2018-00291, IPR2018-00318, IPR2018-00322, IPR2018-00385, and IPR2018-00797 (2019).

Represented Illumina in IPRs challenging patents relating to nucleotide analogues for sequencing-by-synthesis. Obtained final written decisions holding all challenged claims unpatentable.

Natera, Inc. v. Illumina, Inc., Case No. IPR2018-01317 (2019).

Defended Illumina against a petition for IPR regarding a patent for noninvasive prenatal testing. Obtained decision denying petition and rejecting all challenges raised against Illumina’s claims.

Complete Genomics, Inc. v. Illumina Cambridge Ltd., Case Nos. IPR2017-02172 and IPR2017-02174 (2018).

Defended Illumina against petitions for IPR regarding a patent directed to DNA sequencing-by-synthesis. Obtained decisions denying petitions and rejecting all challenges raised against Illumina’s claims.

Aptalis Pharmatech, Inc., Ivax International GMBH v. Apotex Inc., Apotex Corp. (Fed. Cir. 2018).

Represented Apotex in patent litigation involving Apotex’s generic version of Amrix, a product used to treat muscle spasms. On appeal, the Federal Circuit ruled in favor of Apotex. In its ruling, the Court determined the district court’s claim construction was erroneous, and that the proper construction required a continuous outer film surrounding the core containing the drug. The Court vacated the erroneous infringement finding and the injunction that prohibited FDA approval of Apotex’s product, and remanded the case for further proceedings consistent with the correct claim construction.

iCeutica Pty Ltd. and Iroko Pharmaceuticals, LLC v. Lupin Limited and Lupin Pharmaceuticals, Inc., Case No. 1:17-cv-00394 (2018).

Represented the Lupin defendants in a patent infringement action in the District of Maryland on patents relating to meloxicam (the active ingredient in Iroko’s Vivlodex® product.) On February 1, 2018, the U.S. District Court for the District of Maryland granted Lupin’s Motion for Summary Judgement. In its Motion, Lupin argued that prosecution history estoppel applied, legally barring Plaintiffs from asserting that Lupin’s products infringed under the doctrine of equivalents. During prosecution of the patents-in-suit, plaintiffs had repeatedly narrowed the particle size limitations to overcome the prior art and had argued that the claimed particle size was a distinguishing feature over the prior art. In opposition to Lupin’s Motion, plaintiffs argued that prosecution history estoppel did not apply as any amendments made during prosecution were merely tangential to the alleged equivalent. Judge Garbis ruled in favor of Lupin finding that both argument-based and amendment-based prosecution history estoppel applied. As plaintiffs could not prove literal infringement of the particle size limitation and were barred from asserting infringement under the doctrine of equivalents, the case was dismissed.

Illumina, Inc. v. Cornell Research Foundation, Inc., Case IPR2016-00557 (2017).

Represented Illumina in an IPR proceeding challenging a patent relating to assays for DNA detection. Achieved favorable case-dispositive settlement for client after institution of the IPR.

iCeutica Pty Ltd. and Iroko Pharmaceuticals, LLC v. Lupin Ltd. and Lupin Pharmaceuticals, Inc., Case No. 14-cv-01515 (2017).

Represented the Lupin defendants in a patent infringement action in the District of Delaware on patents relating to diclofenac acid (the active ingredient in Iroko’s Zorvolex® product). Achieved favorable case-dispositive settlement for client.

Intelligent Bio-Systems, Inc. v. Illumina Cambridge Ltd., 821 F.3d 1359 (Fed. Cir. 2016) and Case IPR2013-00517 (2015).

Represented Illumina and obtained final IPR written decision and affirmance of IPR final written decision upholding the validity of all challenged claims from a patent directed to DNA sequencing-by-synthesis.

Ariosa Diagnostics, Inc. v. Illumina, Inc., Case IPR2014-01093 (2016).

Represented Illumina in an IPR proceeding defending a patent directed to noninvasive prenatal screening methods. Obtained final written decision upholding the validity of all challenged claims.

Gilead Sciences, Inc. et al. v. Lupin Pharmaceuticals, Inc. et al., Case Nos. 15-cv-01956 and 15-cv-02793 (2016).

Represented the Lupin defendants in a patent infringement action in the District of Maryland on a patent relating to olseltamivir (the active ingredient in Gilead’s Tamiflu® products). Achieved favorable case-dispositive settlement for client.

Forest Laboratories Holdings Ltd., et al v. Apotex Corp., et al., Case Nos. 13-cv-01602 and 13-cv-01604 (2016).

Represented the Lupin defendants in a patent infringement action in the District of Delaware on patents relating to milnacipran hydrochloride (the active ingredient in Forest Laboratories’ Savella® product). Achieved favorable case-dispositive settlement for client following a full bench trial.

Merck Sharp & Dohme Corp. v. Xellia Pharmaceuticals, ApS et al., Appeal No. 2015-1905 (2016).

Represented the Xellia defendants on appeal in a patent infringement action relating to caspofungin diacetate (the active ingredient in Merck’s Cancidas® products). Achieved favorable case-dispositive settlement for client.

Jazz Pharmaceuticals, Inc., et al. v. Amneal Pharmaceuticals, LLC et al., Case Nos. 13-cv-00391 and 15-cv-08229 (2016).

Represented the Ranbaxy defendants in a patent infringement action in the District of New Jersey on patents relating to sodium oxybate (the active ingredient in Jazz’s Xyrem® product) and patents relating to the REMS system for the product. Achieved favorable case-dispositive settlement for client.

Teijin Ltd., et al. v. Lupin Ltd., et al., Case No. 14-cv-00184 (2016).

Represented the Lupin defendants in a patent infringement action in the District of Delaware on a patent relating to febuxostat (the active ingredient in Takeda’s Uloric® product). Achieved a favorable case-dispositive settlement for client.

Roche Molecular Systems Inc. v. Illumina, Inc., Case IPR2015-01091 (2015).

Defended Illumina against a petition for IPR regarding a patent for noninvasive prenatal screening methods. Obtained decision denying petition and rejecting all challenges raised against Illumina’s claims.

Eisai Co., Ltd., et al. v. Lupin Ltd., et al., Case Nos. 13-civ-1279 and 13-civ-1281 (2015).

Represented the Lupin defendants in a patent infringement action in the District of Delaware on patents relating to rufinamide (the active ingredient in Eisai’s Banzel® product). Achieved favorable case-dispositive settlement for client.

Mallinckrodt LLC v. Lupin Ltd. et al., Case No. 12-cv-01087 (2014).

Represented the Lupin defendants in a patent infringement action in the District of Delaware on patents relating to diclofenac sodium (the active ingredient in Nuvo’s Pennsaid® product). Achieved favorable case-dispositive settlement for client.

UCB, Inc., et al. v. Ranbaxy Laboratories, Ltd., et al., Case No. 13-cv-01215 (2014).

Represented the Ranbaxy defendants in a patent infringement action in the District of Delaware on a patent relating to lacosamide (the active ingredient in UCB’s Vimpat® products). Achieved a favorable case-dispositive settlement for client.

Ranbaxy Labs, Ltd. and Ranbaxy v. Vertex Pharms., Inc., Case IPR2013-00024 (2013).

Represented Ranbaxy in one of the first IPR proceedings challenging a patent relating to fosamprenavir (the active ingredient in ViiV's Lexiva® product). Achieved favorable case-dispositive settlement for client after institution of the IPR.

Represented the Ranbaxy defendants in a patent infringement action in the Southern District of New York on patents relating to oxycodone (the active ingredient in Purdue’s Oxycontin® product). Achieved favorable case-dispositive settlement for client.

GlaxoSmithKline v. Anchen Pharmaceuticals et al., Case No. 11-046 (RGA) (MPT) (2011).

Represented the Anchen defendants in patent infringement action in the District of Delaware on a patent relating to pharmaceutical compositions of dutasteride (the active ingredient in GSK’s Avodart® product) and a combination of dutasteride and tamsulosin (the active ingredients in GSK's Jalyn® product). Achieved favorable case-dispositive settlement for client.

Lupin Atlantis Holdings S.A. v. Ranbaxy Labs. Ltd. et al., 2:11-cv-03851 (2011).

Represented defendants in patent infringement action in the Southern District of New York on two patents relating to pharmaceutical compositions of fenofibrate (the active ingredient in Lupin’s Antara® product). Achieved favorable case-dispositive settlement for client.

Roche Palo Alto v. Ranbaxy Labs. Ltd., 2009 U.S. Dist. LEXIS 90804 (D.N.J. 2009).

Represented defendants in patent infringement action in the District of New Jersey on a patent relating to valganciclovir (the active ingredient in Roche’s Valcyte® product). Obtained a successful judgment of noninfringement following trial.

Pfizer Inc. et al. v. Ranbaxy Labs. Ltd. et al., 1:08-cv-00164 (2008).

Represented defendants in patent infringement action in the District of Delaware on two patents relating to methods of making atorvastatin (the active ingredient in Pfizer’s Lipitor® product). Achieved favorable case-dispositive settlement for client.

Pfizer Inc. et al. v. Ranbaxy Labs. Ltd. et al., 1:08-cv-00162 (2008).

Represented defendants in patent infringement action in the District of Delaware on two patents relating to methods of making atorvastatin (one of the active ingredients in Pfizer’s Caduet® product). Achieved favorable case-dispositive settlement for client.

Pfizer Inc. et al. v. Ranbaxy Labs. Ltd. et al., Case No. 1:07-cv-00138 (2007).

Represented defendants in patent infringement action on method patent relating to the use of atorvastatin calcium/amlodipine besylate (the active ingredients in Pfizer’s Caduet® product). Achieved favorable case-dispositive settlement for client.

Pfizer Inc. v. Ranbaxy Labs. Ltd., 457 F.3d 1284 (Fed. Cir. 2006).

Represented defendant and invalidated one of the patents protecting atorvastatin (the active ingredient in Pfizer’s Lipitor®).

Astellas Pharma Inc. et al. v. Ranbaxy Labs. Ltd. et al., Case No. 3:05-cv-02563 (2005).

Represented defendants in patent infringement action in the District of New Jersey on patent relating to tamsulosin (the active ingredient in Astellas’ Flomax® product). On appeal, the case settled prior to a decision by the Court of Appeals for the Federal Circuit.

AstraZeneca AB et al. v. Ranbaxy Labs. Ltd. et al., 3:05-cv-05553 (2005).

Represented defendants in patent infringement action in the District of New Jersey concerning six patents related to esomeprazole magnesium (the active ingredient in AstraZeneca’s Nexium® product). Achieved favorable settlement for client.

Ranbaxy Labs. Ltd. v. Abbott Labs. et al., Case No. 1:04cv8078 (N.D. Ill.).

Represented declaratory judgment plaintiff with respect to clarithromycin. In responding to a motion for preliminary injunction, showed a likelihood that two patents relating to extended release formulations of clarithromycin (the active ingredient in Abbott’s Biaxin XL®) were likely invalid for inequitable conduct.

Ranbaxy Pharms. Inc. v. Apotex, Inc., 350 F.3d 1235 (Fed. Cir. 2003).

Represented declaratory judgment plaintiff and defeated both a motion for temporary restraining order and a motion for preliminary injunction in the district court. Sustained denial of the preliminary injunction on appeal, and on remand obtained summary judgment of noninfringement.

Smithkline Beecham Corp. v. Ranbaxy Labs. Ltd., 03-cv-2158 (D. N.J.).

Represented defendant and obtained favorable settlement relating to valacyclovir (the active ingredient in Glaxo’s Valtrex®).

Glaxo Group Ltd. v. Ranbaxy Pharms. Inc., 262 F.3d 1333 (Fed. Cir. 2001).

Represented defendant and obtained vacature of a preliminary injunction. On remand, the district court conducted a six-week bench trial and granted judgment that defendant did not infringe Glaxo’s patent relating to cefuroxime axetil (the active ingredient in Glaxo’s Ceftin®).

Gart v. Logitech, 254 F.3d 1334 (Fed. Cir. 2001), cert. denied, 122 S. Ct. 921 (2002).

Represented plaintiff patent owner and obtained reversal of noninfringement ruling.

Talbert Fuel Sys. Patents Co. v. Unocal Corp. et al., 275 F.3d 1371 (Fed. Cir. 2002).

Represented defendant and sustained summary judgment of patent noninfringement.

Geneva Pharms., Inc. et al. v. Glaxosmithkline, PLC, 213 F. Supp. 2d 597 (E.D. Va. 2002) and 189 F. Supp. 2d 377 (E.D. Va. 2002).

Awards & Honors

Bill has received multiple awards and has been honored in both national and international forums for his legal accomplishments:

Recognized in the "Best Lawyers 2025 Guide" for Intellectual Property Litigation in Best Lawyers in America (2024)
Recognized for outstanding work in patent law in the 2024 edition of the Intellectual Asset Management (IAM) "Patent 1000 Guide" for Litigation (2024)
Recognized as a Patent Star in Managing IP''s "2024 IP STARS" (2024)
Recognized as a "World IP Leader" by World Intellectual Property Review (WIPR) (2023 - 2024)
Recognized as a "Washington D.C. Super Lawyer" by Super Lawyers magazine for his intellectual property litigation practice (2015 - 2023)
Ranked amongst top ten for Top 100 Most Active ANDA Attorneys Representing
Defendants and 12th for Best Performing ANDA Attorneys Representing Defendants by Patexia Insight's 2021 ANDA Litigation Intelligence Report
Selected by peers for inclusion in The Best Lawyers in America® for his outstanding work in Intellectual Property Litigation (2022 - 2024)
Selected by The Legal 500 "United States" for Patent Litigation (2018-2023) and Patent Prosecution (2018 - 2021)
Recognized as a Patent Star in Managing IP's "IP Stars" Guide for his outstanding intellectual property legal work (2014 - 2023)
Named Top Patent Challenger Attorney 2020 by Docket Navigator
Named a "Life Science Star" by Legal Media Group "LMG Life Sciences" (2012 - 2018 and 2022 - 2023). In 2023, Bill was recognized in the areas of Patent Litigation, Patent Strategy & Management and Hatch-Waxman Litigation. A client praised Bill as a "highly experienced litigator, who can always be relied on to give solid, practical advice". In 2017, Bill was commended by peers as "one of the very excellent lawyers on the generic side". In 2016, he was recognized for his work in cardiovascular drugs, drug formulations, transdermals, biologics, biosimilars, combination products, allergenics, antibiotics, vaccines, and dental devices. Bill was also noted for helping client Ranbaxy receive a favorable decision, allowing the company to market a generic version of Lipitor, the world’s best-selling drug.
Named one of the "World's Leading Patent Professionals" for litigation in the Patent 1000 guide by Intellectual Asset Management (IAM) magazine (2013 - 2018; 2022 - 2023). In the 2018 guide, Bill was recognized for being "well versed in the intracacies of the ANDA process" and commended for his "rare finesse" litgating under the Hatch-Waxman Act.
Nominated by the Managing IP (MIP) Americas Awards 2018 for "Outstanding Litigator - D.C."
Named in Who's Who Legal's 2017 and 2023 editions of the international "Who's Who Legal: Patents" list
Named "Hatch-Waxman Litigator of the Year - Generic" in the 2016 LMG Life Sciences Awards by Legal Media Group (LMG)
Named in the Intellectual Asset Management (IAM) Life Sciences 250 – The World’s Leading Life Sciences Patent Litigators (2010)
Named one of the top 50 intellectual property lawyers under the age of 40 by IP Law & Business magazine (2008)

Articles

William R. Zimmerman and Nathan Engels, The Supreme Court Addresses Amendment-Based Prosecution History Estoppel, OCPLA Newsletter (June, 2002).

William R. Zimmerman, Unifying Markman and Warner-Jenkinson: A Revised Approach To The Doctrine Of Equivalents, 11 Harv. J. L. & Tech. 185 (1997).

Speeches & Seminars

Jonathan S. Caplan, Jennifer L. Fox, Jason Murata, Chuck Sholtz, and William R. Zimmerman. ACI’s 9th Annual Summit on Biosimilars: Navigating through Biosimilars IPRs. (June 25, 2018)

Craig Summers and William R. Zimmerman. Case law update: Recent IP cases that impact your business. IP Impact – Seattle 2012: Innovative Intellectual Property Litigation Strategies. Seattle, WA (February 29, 2012).

Carol Pitzel Cruz and William Zimmerman. In-Depth Review of Recent Decisions and Trends in Hatch-Waxman Litigation. 4th Annual Product and Pipeline Enhancement for Generics Conference: Navigating Regulatory Pathways and Patent Strategies to Ensure Market Sustainability. (July 27, 2011).

Stephen R. Auten, David M. Fox, William R. Zimmerman, and Charles E. Van Horne, Patent Certification/Litigation. Brands, Generics, and Hatch-Waxman: New Challenge; Unabated Controversy, Food and Drug Law Institute (June 24, 2011).

Christopher J. Kelly and William R. Zimmerman. The Master Class on Settling Paragraph IV Disputes: Drafting and Negotiating Strategies for Brand-Names and Generics – A Hands-On, Practical Approach. Paragraph IV Disputes Post-Conference Workshop (May 5, 2011).

William R. Zimmerman. Recent Court Decisions You Need to Know About. IP Impact – Research Triangle Park 2010: Innovative Intellectual Property Strategies for Emerging Technology Companies. Chapel Hill, NC (September 23, 2010).

William R. Zimmerman. 3rd Annual Product and Pipeline Enhancement for Generics Conference: Navigating Regulatory Pathways and Patent Strategies to Ensure Market Sustainability. (June 28-30, 2010).

William R. Zimmerman Recent Developments in Patent Law. IP Impact- Research Triangle 2009: Innovative Intellectual Property Strategies for Emerging Technology Companies. Chapel Hill, NC (September 29, 2009).

Kennth R. Adamo, Eric M. Albritton, Cynthia E. Kernick, Charles F. Schill, and William R. Zimmerman. Litigating in Popular Jurisdictions. BNA Legal and Business Edge: Using Today’s Patent Laws to Protect Tomorrow’s Technology – New Litigation Strategies (October 6, 2008).

William R. Zimmerman. Life Cycle Management Considerations. The Increasing Role of Antitrust Principles in Defining Patent Rights. IPO Conference (June 9, 2008)

Brian Way, Jeremiah Chan, William R. Zimmmeran, and Adeel Akhtar. Recent Supreme Court Cases (and Seagate). IP Impact Seminar 2007: Intellectual Property Law Gets Down to Business (October 11, 2007).

William R. Zimmerman, Complying with Standards for Expert Work Product, Law Seminars International (March 20, 2006).

William R. Zimmerman, Coordinating Worldwide Pharmaceutical Disputes, Henry Stewart Conference (September 28, 2005).

Don W. Martens and William R. Zimmerman, Recent Decisions In Patent Law, presented by Don W. Martens to the San Diego Intellectual Property Law Association (October 24, 2002), published at www.sdipla.org.

William R. Zimmerman, The Patent Year In Review, presented by William R. Zimmerman to the OCPLA/SDIPLA Spring Seminar (March 24, 2002).

Don W. Martens and William R. Zimmerman, Perspective Impact Of Recent Decisions Affecting Intellectual Property Litigation, presented by

Don W. Martens to the CLE International Conference On Intellectual Property Issues In Biotechnology Law (March 14-15, 2002).

Don W. Martens and William R. Zimmerman, Recent Developments In Claim Interpretation And Other Patent Law Issues Relating To Biotechnology, A Presentation to Genentech (February 8, 2002).

Don W. Martens and William R. Zimmerman, The Recent Narrowing Of Literal Claim Scope And The Permissible Range Of Equivalents In The United States, Patent World (Nov. 2001, No. 137).

Don W. Martens and William R. Zimmerman, Recent Patent Decisions, presented by Don W. Martens to the 26th Annual IP Institute, IP Section of the State Bar of California (Nov. 16-17, 2001).

Don W. Martens and William R. Zimmerman, The Recent Narrowing Of Literal Claim Scope And The Permissible Range Of Equivalents, presented by Don W. Martens to the Joint Session AIPLA and the IP Entertainment Law Committee of the IBA Section on Business Law (Cancun, Mexico Nov. 2, 2001)

Don W. Martens and William R. Zimmerman, The Recent Narrowing Of Literal Claim Scope And The Permissible Range Of Equivalents, presented by Don W. Martens to the San Francisco Intellectual Property Law Association (September 19, 2001).

Don W. Martens and William R. Zimmerman, The Recent Narrowing Of Literal Claim Scope And The Permissible Range Of Equivalents, presented by Don W. Martens on behalf of the American Intellectual Property Law Association in Moscow, Russia (June 5-6, 2001).

Karen Vogel Weil and William R. Zimmerman, Recent Developments In Invalidity Under 35 U.S.C. § 112 At The United States Court Of Appeals For The Federal Circuit, American Intellectual Property Law Association 2001 Road Show -- Advanced Patent Litigation Seminar (presenter in Boston, MA June 1, 2001; Chicago, IL June 8, 2001; Los Angeles, CA June 22, 2001).

Karen Vogel Weil and William R. Zimmerman, Recent Developments In Invalidity Under 35 U.S.C. § 112 At The United States Court Of Appeals For The Federal Circuit, presented to the Orange County Patent Law Association (July 18, 2001).

Don W. Martens and William R. Zimmerman, Recent Patent Decisions, 25th Annual Intellectual Property Institute, The Intellectual Property Section of the State Bar of California (Nov. 10, 2000).

Don W. Martens and William R. Zimmerman, Recent Patent Decisions, USPTO Academy (July 18, 2000).