Written Description

The written description requirement asks whether the specification demonstrates that the inventor actually possessed the claimed invention as of the filing date. It is distinct from enablement: a specification may teach a skilled artisan how to make and use something without showing that the inventor had conceived the full breadth of what is claimed. The requirement bites hardest where claims were amended during prosecution to cover a competitor's product, or where a genus is claimed on the strength of a few disclosed species. The opinions collected here address written description as a validity defence, at summary judgment and after trial, and its role in policing claim scope.

62 opinions and orders.

• April 16, 2026 Fed. Cir. Teva Pharmaceuticals International GmbH v. Eli Lilly and Company, No. 24-1094 (Fed. Cir. Apr. 16, 2026) Reversed in Part
• April 6, 2026 E.D. Tex. EireOg Innovations Ltd. v. Cisco Systems Inc., No. 2:24-cv-00224 (E.D. Tex. Apr. 6, 2026) Denied
• April 6, 2026 E.D. Tex. EireOg Innovations Ltd. v. Cisco Systems Inc., No. 2:24-cv-00224 (E.D. Tex. Apr. 6, 2026) Denied
• March 25, 2026 E.D. Tex. General Access Solutions, Ltd. v. T-Mobile US, Inc. et al, No. 2:23-cv-00158 (E.D. Tex. Mar. 25, 2026) Denied
• February 1, 2026 E.D. Tex. Vasu Holdings, LLC v. Samsung Electronics Co., Ltd. et al, No. 2:24-cv-00034 (E.D. Tex. Feb. 1, 2026) Denied
• December 2, 2025 Fed. Cir. Seagen Inc. v. Daiichi Sankyo Company, Ltd., No. 23-2424 (Fed. Cir. Dec. 2, 2025) Reversed
• November 18, 2025 Fed. Cir. Duke University v. Sandoz Inc., No. 24-1078 (Fed. Cir. Nov. 18, 2025) Reversed
• August 28, 2025 Fed. Cir. Google LLC v. Sonos, Inc., No. 24-1097 (Fed. Cir. Aug. 28, 2025) Reversed in Part
• August 8, 2025 Fed. Cir. Mondis Technology Ltd. v. LG Electronics Inc., No. 23-2117 (Fed. Cir. Aug. 8, 2025) Reversed
• April 20, 2025 E.D. Tex. Headwater Research LLC v. Samsung Electronics America, Inc. et al, No. 2:23-cv-00103 (E.D. Tex. Apr. 20, 2025) Adopted
• April 1, 2025 E.D. Tex. Headwater Research LLC v. Samsung Electronics America, Inc. et al, No. 2:23-cv-00103 (E.D. Tex. Apr. 1, 2025) Denied
• March 6, 2025 Fed. Cir. ImmunoGen, Inc. v. Stewart, No. 23-1762 (Fed. Cir. Mar. 6, 2025) Affirmed
• January 29, 2025 Fed. Cir. Regeneron Pharmaceuticals, Inc. v. Mylan Pharmaceuticals Inc., No. 24-2009 (Fed. Cir. Jan. 29, 2025) Affirmed
• July 31, 2024 E.D. Tex. Headwater Research LLC v. Samsung Electronics America, Inc. et al, No. 2:22-cv-00422 (E.D. Tex. July 31, 2024) Denied
• July 17, 2024 E.D. Tex. Evolved Wireless, LLC v. Samsung Electronics Co., Ltd. et al, No. 2:21-cv-00033 (E.D. Tex. July 17, 2024) Denied
• January 2, 2024 Fed. Cir. PureCircle USA Inc. v. SweeGen, Inc., No. 22-1946 (Fed. Cir. Jan. 2, 2024) Affirmed
• May 24, 2022 E.D. Tex. Firtiva Corporation v. Funimation Global Group, LLC, No. 2:21-cv-00111 (E.D. Tex. May 24, 2022) Granted in Part
• April 22, 2022 Fed. Cir. Ascion, LLC v. Ashley Furniture Industries, Inc., No. 21-1857 (Fed. Cir. Apr. 22, 2022) Vacated & Remanded
• August 26, 2021 Fed. Cir. Juno Therapeutics, Inc. v. Kite Pharma, Inc., No. 20-1758 (Fed. Cir. Aug. 26, 2021) Reversed
• July 14, 2021 Fed. Cir. Flash-Control, LLC v. Intel Corporation, No. 20-2141 (Fed. Cir. July 14, 2021) Affirmed
• July 8, 2020 Fed. Cir. Via Vadis, LLC v. Blizzard Entertainment, Inc., No. 19-2269 (Fed. Cir. July 8, 2020) Affirmed in Part
• July 1, 2020 Fed. Cir. Immunex Corporation v. Sandoz Inc., No. 20-1037 (Fed. Cir. July 1, 2020) Affirmed
• April 3, 2020 Fed. Cir. Taylor v. Iancu, No. 18-1070 (Fed. Cir. Apr. 3, 2020) Affirmed
• April 3, 2020 Fed. Cir. Taylor v. Iancu, No. 18-1048 (Fed. Cir. Apr. 3, 2020) Affirmed
• December 27, 2019 Fed. Cir. Persion Pharmaceuticals LLC v. Alvogen Malta Operations Ltd., No. 18-2361 (Fed. Cir. Dec. 27, 2019) Affirmed
• October 30, 2019 Fed. Cir. Idenix Pharmaceuticals LLC v. Gilead Sciences Inc., No. 18-1691 (Fed. Cir. Oct. 30, 2019) Affirmed in Part
• September 23, 2019 Fed. Cir. OrthoAccel Technologies, Inc. v. Propel Orthodontics, LLC, No. 18-1534 (Fed. Cir. Sept. 23, 2019) Affirmed
• August 15, 2019 Fed. Cir. Nalpropion Pharmaceuticals, v. Actavis Laboratories FL, Inc., No. 18-1221 (Fed. Cir. Aug. 15, 2019) Affirmed in Part
• August 7, 2019 Fed. Cir. Nuvo Pharmaceuticals v. Dr. Reddy's Laboratories Inc., No. 17-2487 (Fed. Cir. Aug. 7, 2019) Reversed
• June 17, 2019 Fed. Cir. Forum US, Inc. v. Flow Valve, LLC, No. 18-1765 (Fed. Cir. June 17, 2019) Affirmed
• May 15, 2019 Fed. Cir. Nuvo Pharmaceuticals v. Dr. Reddy's Laboratories Inc., No. 17-2473 (Fed. Cir. May 15, 2019) Reversed in Part
• March 18, 2019 Fed. Cir. Sprint Communications Company v. Time Warner Cable, Inc., No. 17-2247 (Fed. Cir. Mar. 18, 2019) Affirmed
• November 30, 2018 Fed. Cir. Sprint Communications Company v. Time Warner Cable, Inc., No. 17-2247 (Fed. Cir. Nov. 30, 2018) Affirmed in Part
• September 27, 2018 E.D. Tex. GeoDynamics, Incorporated v. DynaEnergetics US, Inc., No. 2:17-cv-00371 (E.D. Tex. Sept. 27, 2018) Denied
• May 21, 2018 Fed. Cir. D Three Enterprises, LLC v. SunModo Corporation, No. 17-1909 (Fed. Cir. May 21, 2018) Affirmed
• May 17, 2018 E.D. Tex. Kaist IP US LLC v. Samsung Electronics Co., Ltd., et al, No. 2:16-cv-01314 (E.D. Tex. May 17, 2018) Granted in Part
• April 13, 2018 Fed. Cir. Vanda Pharmaceuticals Inc. v. West-Ward Pharmaceuticals, No. 16-2707 (Fed. Cir. Apr. 13, 2018) Affirmed
• October 5, 2017 Fed. Cir. Amgen Inc. v. Sanofi, No. 17-1480 (Fed. Cir. Oct. 5, 2017) Reversed in Part
• August 25, 2017 E.D. Tex. Erfindergemeinschaft UroPep GbR v. Eli Lilly & Co., No. 2:15-cv-1202-WCB (E.D. Tex. Aug. 25, 2017) Denied
• June 27, 2017 Fed. Cir. Stanford University v. The Chinese Univ. of Hong Kong, No. 15-2011 (Fed. Cir. June 27, 2017) Vacated & Remanded
• October 21, 2016 E.D. Tex. Erfindergemeinschaft UroPep GbR v. Eli Lilly and Company et al, No. 2:15-cv-01202 (E.D. Tex. Oct. 21, 2016) Granted in Part
• September 29, 2016 E.D. Tex. PerdiemCo, LLC. v. Industrack LLC, No. 2:15-cv-00727 (E.D. Tex. Sept. 29, 2016) Adopted
• September 20, 2016 Fed. Cir. Yeda Research and Development v. Abbott GmbH & Co. KG, No. 15-1662 (Fed. Cir. Sept. 20, 2016) Affirmed in Part
• August 15, 2016 Fed. Cir. ScriptPro LLC v. Innovation Associates, Inc., No. 15-1565 (Fed. Cir. Aug. 15, 2016) Reversed in Part
• February 10, 2016 Fed. Cir. Driessen v. Sony Music Entertainment, No. 15-2050 (Fed. Cir. Feb. 10, 2016) Affirmed
• August 21, 2015 E.D. Tex. Motio, Inc. v. BSP Software LLC, No. 4:12-cv-00647 (E.D. Tex. Aug. 21, 2015) Denied
• August 4, 2015 Fed. Cir. Allergan, Inc. v. Sandoz Inc., No. 14-1275 (Fed. Cir. Aug. 4, 2015) Affirmed
• April 3, 2015 Fed. Cir. Vasudevan Software, Inc. v. MicroStrategy, Inc., No. 14-1094 (Fed. Cir. Apr. 3, 2015) Affirmed in Part
• November 17, 2014 Fed. Cir. Antares Pharma Inc. v. Medac Pharma Inc., No. 14-1648 (Fed. Cir. Nov. 17, 2014) Affirmed
• August 6, 2014 Fed. Cir. ScriptPro, LLC v. Innovation Associates, No. 13-1561 (Fed. Cir. Aug. 6, 2014) Reversed
• July 1, 2014 Fed. Cir. AbbVie Deutschland GmbH & Co. v. Janssen Biotech, Inc., No. 13-1338 (Fed. Cir. July 1, 2014) Affirmed
• June 27, 2014 Fed. Cir. Lochner Technologies, LLC v. Vizio, Inc., No. 13-1551 (Fed. Cir. June 27, 2014) Vacated & Remanded
• March 18, 2014 Fed. Cir. Alcon Research, Ltd. v. Barr Laboratories, Inc., No. 12-1340 (Fed. Cir. Mar. 18, 2014) Affirmed in Part
• February 24, 2014 Fed. Cir. GlaxoSmithKline LLC v. Banner Pharmacaps, Inc., No. 13-1593 (Fed. Cir. Feb. 24, 2014) Affirmed
• February 18, 2014 Fed. Cir. Butamax(TM) Advanced Biofuels v. Gevo, Inc., No. 13-1342 (Fed. Cir. Feb. 18, 2014) Reversed in Part
• February 6, 2014 Fed. Cir. Pfizer Inc. v. Teva Pharmaceuticals USA, No. 12-1576 (Fed. Cir. Feb. 6, 2014) Affirmed
• October 29, 2013 Fed. Cir. Synthes USA, LLC v. Spinal Kinetics, Inc., No. 13-1047 (Fed. Cir. Oct. 29, 2013) Affirmed
• August 30, 2013 Fed. Cir. Trading Technologies Intl v. Open E Cry, LLC, No. 12-1583 (Fed. Cir. Aug. 30, 2013) Reversed
• July 22, 2013 Fed. Cir. Novozymes A/S v. Dupont Nutrition Biosciences, No. 12-1433 (Fed. Cir. July 22, 2013) Affirmed
• February 27, 2012 E.D. Tex. NovelPoint Learning LLC v. Leapfrog Enterprises, Inc. et al, No. 6:10-cv-00229 (E.D. Tex. Feb. 27, 2012) Denied
• November 13, 2006 E.D. Tex. Commonwealth Scientific and Industrial Research Organisation v. Buffalo Technology (USA), Inc et al, No. 6:06-cv-00324 (E.D. Tex. Nov. 13, 2006) Granted in Part
• June 13, 2006 E.D. Tex. The Rockfeller University et al v. Centocor, Inc et al, No. 2:04-cv-00168 (E.D. Tex. June 13, 2006) Denied