Roshan concentrates his practice in patent litigation, prosecution, counseling related to pharmaceutical, biosimilars, biotechnology, medical device, chemical products and electronic materials.

Roshan has broad litigation experience, including district court litigation, contested AIA proceedings, e.g., Reexamination and Inter Partes Review (IPR) at the Patent Trial and Appeal Board (PTAB) in the United States Patent and Trademark Office (USPTO), International Trade Commission (ITC), and appellate matters.

Roshan has particular experience on issues arising under the Hatch-Waxman Act. He has expertise in developing strategies on issues of patentability, infringement, validity and enforceability. He has represented prominent generic and brand pharmaceutical companies at both the trial and appellate levels in matters involving Silenor® (doxepin), Vyvanse (lisdexamfetamine dimesylate), Vimovo (naproxen/esomeprazole magnesium), Lyrica (pregabalin), Yaz (Drospirenone/Ethinyl Estradiol), Nexium (esomeprazole), Xarelto (rivaroxaban), Antara (Fenofibrate) and Rayos (Prednisone). Roshan also assists with the firm’s patent counseling and IP due diligence matters. He has extensive experience performing IP due diligence as part of corporate mergers and acquisitions, analyzing patent landscape and preparing patent non-infringement and invalidity opinions.

Prior to joining Taft, Roshan was an associate at Leydig, Voit and Mayer, Ltd., a prominent IP boutique in Chicago. Before practicing law, he was a research scientist at Los Alamos National Laboratory in New Mexico, where his investigation on materials for hydrogen storage technology received a patent. His work received grant funding from the National Science Foundation, Department of Energy and NASA.

Roshan received his B.A. in chemistry, Phi Beta Kappa, from Grinnell College in 2001 and his Ph.D. from the University of North Carolina at Chapel Hill in 2006. He earned his J.D., cum laude, from Northwestern University School of Law, where he was a notes and comments editor for the Northwestern Journal of Technology and Intellectual Property.

Since 2014, Roshan has been recognized as a Rising Star by Illinois Super Lawyers. He has also been named an Emerging Lawyer by Leading Lawyers Network. Roshan was named one of the “40 Illinois Attorneys Under 40 to Watch” for 2016 by Law Bulletin, publishers of Chicago Lawyer magazine and the Chicago Daily Law Bulletin. He volunteers at various Chicago non-profits and has served in the board of directors for Apna Ghar – Our Home, a Chicago non-profit that provides holistic services and conducts advocacy across immigrant communities to end gender violence.


  • U.S. Pat. No. 8,613,902, Hydrogen Production Using Ammonia Borane (Issued Dec. 24, 2013).
  • U.S. Pat. No. 7,713,506, Metal Aminoboranes (Issued May 11, 2010).


All Service Areas


  • Northwestern University School of Law (2011)
  • University of North Carolina at Chapel Hill, Ph.D. (2006)
  • Grinnell College (B.S. Chemistry) (2001)


  • Federal - United States Patent and Trademark Office
  • Federal - U.S. Court of Appeals for the Federal Circuit
  • Federal - Northern District of Illinois
  • State - Illinois

Speeches and Publications

Articles and Publications

  • Fed. Circ. Skinny Label Ruling Guides on Infringement Claims,” with co-author Luke Shannon, Law360, July 5, 2024.
  • Obviousness Analysis Trends In Pharma Patent Cases,” with co-author Joseph Bennett-Paris, Law360, May 3, 2019.
  • Numbers Don’t Lie – Vivlodex (meloxicam) case on Doctrine of Equivalents,” LinkedIn, February, 14, 2018.
  • Interpreting a Patent Is Not So ‘Plain and Ordinary’ After All,” co-author with Richard Ruzich, Law360, April 19, 2016.
  • “The Importance of Apportionment in Calculating Damages for Patent Infringement,” Chicago Daily Law Bulletin, March 16, 2015.
  • Edward Manzo, Roshan P. Shrestha, et al. Patent Claim Construction in the Federal Circuit, West (2014).
  • “Overcoming The PTAB Checklist In An IPR Petition,” Law360, July 1, 2014.
  • “Implementation of litigation holds can avoid liability over spoliation,” Chicago Daily Law Bulletin, June 16, 2014.
  • “The boundaries of discoverable information,” Chicago Daily Law Bulletin, March 20, 2014.
  • H. Diyabalange, R. P. Shrestha et al., Potassium(I) Amidotrihydroborate: Structure and Hydrogen Release, 132 J. Am. Chem. Soc. 34, 11836 (2010).
  • R. P. Shrestha, et al., Catalytic Dehydrogenation of Ammonia Borane in Non-Aqueous Medium, 34 Int’l J. Hydrogen Energy 6, 2616 (2009).
  • H. H. Divyabalanage, R. P. Shrestha et al. Calcium Ammonia Borane—A hydrogen storage Material, 46 Angew. Chem. Int. Ed., 8995 (2007).
  • Y. X. Li, R.P. Shrestha et al. Study of poly(vinylidene fluoride-trifluoroethylene) as a Potential Organic High K Gate Dielectric, 25 JVST-A, 275 (2007).
  • R. P. Shrestha, D. Yang et al. Characterization and Optimization of a P-channel Poly (o-methoxyaniline) Based Thin Film Transistor, 24 JVST-B, 2731 (2006).
  • D. Yang, R.P. Shrestha, et al., Mobility Study of a New Naphthalenetetracarboxylic Diimide Derivative by Ellipsometry, 24 JVST-B, 2653 (2006).
  • R. P. Shrestha et al., Ellipsometry Study of poly(o-methoxyaniline) Thin Films, 500 Thin Solid Films, 252 (2006).
  • D. Yang, R. P. Shrestha et al., Optical Properties of N,N’-bis (3-phenoxy-3-phenoxy-phenoxy)-1,4,5,8-naphthalenetetracarboxylic diimide by Spectroscopic Ellipsometry, 500 Thin Solid Films, 9 (2006).
  • Y.X. Li, L. Yan, R.P. Shrestha, et al., A Study of the Optical and Electronic Properties of Poly (Vinylidene Fluoride-Trifluoroethylene) Copolymer Thin Film, 513 Thin Solid Films, 283 (2006).
  • L. Yan, R. P. Shrestha et al. MgO as a High-k Gate Dielectric, 88 Applied Physics Letters 14, 142901 (2006).

Speaking Engagements

  • “Strategic Insights: Maintaining the 180-Day Marketing Exclusivity and a Later Filer’s Path to Trigger Forfeiture,” 13th Annual Pharma IPR Conference, Mumbai, India, March 5, 2024.
  • “Recent Cases and Trends in US Litigation,” IpEssentia webinar, November 27, 2023.
  • “Recent Cases and Trends in US Litigation,” IpEssentia webinar, November 8, 2022.
  • “Section 112 Challenges – Amgen v. Sanofi,” 11th Annual Pharma IPR Conference, Mumbai, India, September 14-16, 2022.
  • “U.S. Pharma Litigation – Judgement on the Pleadings,” Global Dialogue on Intellectual Property Strategies seminar, Oct. 7, 2020 (with Steve Auten)
  • “Rule 12 Motions in Hatch Waxman Cases in 2019” 9th Annual Pharma IPR Conference, Mumbai, India, March 4-6, 2020.
  • Panel moderator, “Advancement to Partnership” 6th Annual Minority Bar CLE Conference, Chicago, June 21, 2018.
  • “Materials Issues in a Hydrogen Economy: Proceedings of the International Symposium,” Richmond, Va., 2007.
  • “Optical and Interfacial Electronic Properties of Spin Cast Poly(o-methoxyaniline) (POMA) Thin Films and Thin Film Transistors,” American Vacuum Society (AVS) 52nd International Symposium, Boston, Mass., 2005.
  • “MgO as a High-k Gate Dielectric,” American Vacuum Society (AVS) 52nd International Symposium, Boston, Mass., 2005.
  • “Optical and Electronic Properties of Poly (o -methoxyaniline)(POMA) for Organic FET Applications,” American Vacuum Society (AVS) 50th International Symposium, Baltimore, Md., 2003.
  • “An Optical and Electronic Properties Study of a Stable n-Type Organic Semiconductor,” American Vacuum Society (AVS) 50th International Symposium, Baltimore, Md., 2003.

Professional Affiliations

  • Intellectual Property Law Association of Chicago