Patenting Polymorphs: Opportunities and Challenges

Proving Validity and Patentability vs. Proving Infringement in Litigation

A live 90-minute premium CLE video webinar with interactive Q&A

This program is included with the Strafford CLE Pass. Click for more information.
This program is included with the Strafford All-Access Pass. Click for more information.

Tuesday, May 2, 2023

1:00pm-2:30pm EDT, 10:00am-11:30am PDT

Early Registration Discount Deadline, Friday, April 7, 2023

or call 1-800-926-7926

The CLE webinar will guide patent counsel on patenting polymorphs from drafting through patent prosecution and enforcement. The panel will further examine lessons learned from the case law and offer strategies to overcome the potential challenges.


The development of pharmaceutical products for FDA approval in the U.S. is often expensive and unpredictable. Compositions and formulations may evolve and, as developed over time, may be separately patentable over earlier U.S. patent filings and might offer many years of additional patent exclusivity. Crystal forms are generally complicated and unpredictable, which can be determinative when considering obviousness and inherent anticipation. However, such arguments might negatively affect written description support of certain claims.

Different crystal forms may have different physicochemical properties that can be claimed. These elements can impact patentability/validity arguments as well as infringement arguments. For example, characterizing information such as IR, Raman, NMR, X-ray, DSC, density, cell parameters, melting point, color, and intensity in a claim may be considered elements of the claim that will need to be proven to show infringement.

The panel will use three recent cases to discuss the opportunities and challenges presented by claiming polymorphs: Gilead Sciences Inc. v. Apotex Inc., (D. Del. 2021); Amgen Inc. v. Sandoz Inc., (D. N.J.), Judge Shipp of the District Court of New Jersey; and BMS v. Sigmapharm Labs. L.L.C., (Fed. Cir. 2021). They will also reference two crystal patents relating to the Allegra product having claims of particular interest. These decisions and the exemplary Allegra patents are excellent examples of the detail-oriented nature of polymorph U.S. patent applications, their prosecution, and litigation, particularly in the ANDA context.

Crystal forms may require considerations involving balancing the ability to prove validity/patentability against proving infringement in litigation. Think through the pros and cons of the following types of claims, for example:

  • Claim(s) that simply refer to the unique crystal form(s)
  • Claim(s) having some characterization data that uniquely identifies the crystal form(s)
  • Claims drawn to process(es) of making the unique crystal form(s)

Consideration of Section 112(f) means-plus-function claims might also be useful. By using a linking table to a specific active ingredient crystal, the claim could, in the language of 112(f), be construed to cover the corresponding structure, material, or acts described in the specification (i.e., the specific crystal disclosed) and equivalents thereof. 112(f) equivalents would be literal equivalents, not equivalents under the doctrine of equivalents.

Listen as our authoritative panel of patent attorneys examines patenting drug formulations from drafting through patent prosecution and enforcement. The panel will further explore lessons learned from the case law and offer strategies to overcome the potential challenges.



  1. Patenting polymorphs
    1. Obviousness
    2. Inherent anticipation
    3. 112(a) and (b) issues
  2. Recent decisions and case study
  3. Proving validity/patentability vs. proving infringement in litigation
  4. Best practices


The panel will review these and other vital issues:

  • How to claim the solid-state crystal form in the composition after formulation
  • How to characterize crystal forms by various, suitable, and sufficient experimental parameters, if needed, to distinguish them over other forms known in the art
  • Consider including the experimental conditions used to produce the new crystal forms in the specification
  • Are there potential technical advantages of the claimed crystal forms?


Browning, Paul
Paul W. Browning, Ph.D.

Finnegan Henderson Farabow Garrett & Dunner

Dr. Browning focuses on patent litigation and appeals. He has led teams as first chair at trial, at Markman...  |  Read More

Irving, Thomas
Thomas L. Irving

Finnegan Henderson Farabow Garrett & Dunner

Mr. Irving has 35 years of experience in the field of IP law. His practice includes due diligence, patent prosecution,...  |  Read More

Issac, Roy
Roy Issac

Senior IP Counsel
Bristol Myers Squibb

Mr. Issac is Senior IP Counsel at Bristol Myers Squibb. He has served as in-house counsel for Allergan and Gilead...  |  Read More

MacAlpine, Jill
Jill K. MacAlpine, Ph.D.

Finnegan Henderson Farabow Garrett & Dunner

Dr. MacAlpine practices patent procurement, due diligence investigations, opinion work, and client counseling,...  |  Read More

Attend on May 2

Early Discount (through 04/07/23)

Cannot Attend May 2?

Early Discount (through 04/07/23)

You may pre-order a recording to listen at your convenience. Recordings are available 48 hours after the webinar. Strafford will process CLE credit for one person on each recording. All formats include course handouts.

To find out which recorded format will provide the best CLE option, select your state:

CLE On-Demand Video