Clif is a registered patent attorney and litigator with over 35 years of experience. He helps clients obtain, enforce, and leverage patent and trademark rights and defend against infringement challenges. He also represents clients on trade secret, trade dress, and copyright matters, and provides opinions on intellectual property availability, validity, freedom to operate, and infringement. He litigates patent and trademark disputes before the federal courts, the International Trade Commission, the USPTO’s Patent Trial and Appeal Board, and USPTO’s Trademark Trial and Appeal Board.

Clif’s accomplishments and qualifications include:

  • Lead trial and appellate counsel for patent owner Ecolochem, Inc., against Southern California Edison, resulting in precedent-setting Federal Circuit decision on nonobviousness.
  • Represented Fortune 500 life sciences company in one of the first Post-Grant Review (PGR) proceedings before the Patent Trial and Appeal Board.
  • Manager of a National Institutes of Health patent portfolio of over 500 chemistry and biotech applications.
  • Prosecuted patents in chemical engineering that withstood competitors’ chal...
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  • Distinctions
    • IP Star, Patents, Washington, D.C., Managing Intellectual Property survey, 2013-present
    • IP Star, Trademarks, Washington, D.C., Managing Intellectual Property survey, 2013-present
    • Selected to the Washington, D.C. Super Lawyers list, 2012-present
    • AV® “Preeminent” Rating by Martindale-Hubbell 1986-present
  • Professional Associations
    • Bar Association of the District of Columbia (Chaired IP Law Section)
    • Bar Association of D.C. Foundation (Member, Board of Trustees)
    • American Bar Association (Chaired Committee 601, Federal IP Litigation and Patent Claim Interpretation Subcommittee)
    • Intellectual Property Owners Association (Member, PTAB Practice Committee)
    • American Intellectual Property Law Association
    • Patent Lawyers Club of Washington
  • Representative Transactions
    • Won eight-figure damages award and $4M in attorneys’ fees as lead trial and appellate counsel for Ecolochem, Inc., owner of patented deoxygenation process, after 10-year precedent-setting infringement battle with Fortune 500 Southern California Edison. (C.D. Cal., Fed. Cir.)
    • Negotiated favorable settlement as lead counsel for U.S.-based WesTech Engineering, Inc. in mediation of patent infringement action brought by global water treatment giant Veolia involving rotary disc filters. (E.D.N.C.)
    • Successfully defended the United States’ largest office supply retailer as lead counsel in patent infringement action brought by leading office supply manufacturer concerning 3-ring binder mechanisms. (D. Del.)
    • Obtained decision by USPTO’s Patent Trial and Appeal Board to institute Post Grant Review of Becton Dickinson’s patent for sepsis diagnosis, representing competitor Thermo Fisher Scientific, Inc. and its German subsidiary. (USPTO)
    • Lead counsel in defense of large U.S. specialty chemical manufacturer in patent infringement action brought by USALCO, LLC for alleged infringement of patented process for manufacturing polyaluminum sulfate. (D. Md.)
    • Co-counsel representing major Swedish forensics software provider in trade secret misappropriation and copyright infringement action brought by a leading Israeli forensics software competitor. (E.D. Va.)
    • Defended one of the nation’s largest federal credit unions as lead counsel in action brought by TQP Development, in which TQP alleged that client’s website infringed encryption patent. (E.D. Va.)
    • Lead patent trial counsel for distributors of e-cigarettes in two trials before International Trade Commission over alleged infringement of e-cigarette patents brought by JUUL Labs. Favorable settlement reached for clients after presenting opening argument at start of second trial. (USITC)
    • Brought suit and stopped use of Diamond logo on fasteners by Fullco Industries that conflicted with client FM Approvals LLC’s use of well-known “FM” in Diamond certification mark for loss prevention products. (D.R.I.)
    • Brought suit for trademark infringement and unfair competition as lead counsel on behalf of FM Approvals and parent, worldwide insurer FM Global. Stopped misleading certification claims by nationwide pallet pooling system operator, iGPS. (M.D. Fl.)
    • Negotiated favorable settlement midway through jury trial as lead trial counsel for well-known tool and hardware company, Red Devil, Inc., in trademark and trade dress infringement action brought by Clark Tile over color-coding system for trowels. (N.D. Ill.)
    • Co-trial counsel in patent infringement action by client Benchmark for competitor’s infringement of patent for arcade amusement game. After five-day jury trial, jury found patent valid and infringed, with favorable settlement before damages phase of trial. (S.D. Fla.)
    • Defended one of world’s leading paper shredder manufacturers, Michilin of Taiwan, against infringement charge by inventor of shredder lubrication sheets, instituted inter partes reexamination at USPTO that resulted in cancellation of asserted patent claims and dismissal of lawsuit. (D. Utah)
    • Trial counsel for high-IQ organization American Mensa in trademark dilution action over famous MENSA mark. Defendant British drug development company stopped use of accused mark to avoid appellate review of lower court’s decision on dilution, which lower court vacated after trial. (D. Md.)
    • Won seven figures in awards and settlements as lead trial counsel for Ecolochem in different infringement actions over patented deoxygenation process by competitors Arrowhead Industrial Water and Mobile Water Technology. (N.D. Ill. and E.D. Ark.)
    • Defended Taiwanese chip manufacturer, Powerchip Semiconductor, in suit by Texas Instruments for alleged breach of a patent license and over $150,000,000 in damages. Matter settled on favorable terms after summary judgment briefing was completed. (S.D. N.Y.)
    • Represented large German company, Software AG, in patent infringement action against U.S. competitor BEA Systems, Inc. for infringement of enterprise software patent, resulting in favorable settlement. (D. Del.)
    • Co-counsel for Johnson & Johnson Pharmaceutical in patent infringement action against Barr Laboratories over oral contraceptive, resulting in summary judgment and injunctive relief for client. (D. N.J.)
    • Defended Porex Technologies in patent infringement action against competitor Labcon, Inc. involving pipette tips used in polymerase chain reaction (PCR) laboratory techniques, resulting in favorable settlement after summary judgment in client’s favor. (N.D. Ga.)
    • Represented Red Devil, Inc. as lead counsel in hearing to determine if client had breached earlier settlement agreement involving competitor Sashco’s patent for caulk. Court ruled in client’s favor. (D. Colo.)
    • Patent matters have dealt with a variety of technologies, including: Alloys, autoimmune disease treatment, banking and business methods, catalysis, caulks and sealants, chemical manufacture, coatings, consumer products, cranes, data extraction, data streaming, diagnostics, e-cigarettes, encryption, filtration, fire prevention, green technology, hand and power tools, hardware, laboratory equipment, LEDs, lubricants, measurement and detection instruments, medical devices, metrology, microorganism recovery, mixing equipment, office machines, oil and gas, packaging, pharmaceuticals, plastics, power generation, semiconductors, shipping containers, encryption software, enterprise software, forensics software, storm water treatment, TENS devices, and water and wastewater treatment equipment and processes.
  • Presentations
    • “Ethical Considerations in Intellectual Property,” 2022 Tri-Association Conference (AWWA, CWEA and WWOA), Ocean City, MD, September 2022
    • “ETFs and Alts: What’s Around the Corner?,” Thompson Hine Investment Management Conference involving actively managed ETF (fintech) technology, NY, NY, September 2019
    • “Protection of Proprietary Technology throughout the Supply Chain: Patents and Trade Secrets,” GlobalChem 2015, Baltimore, MD, March 2015
    • “Water Projects: Hot Topics in Finance & Innovation,” 2014 Sustainable Manufacturer & Water 2.0 Conference, Chicago, IL, May 2014
    • “Intellectual Property Audits: The Purpose, Importance, and Cost,” National Meeting of the American Chemical Society, March 2014
    • “Dispute Avoidance and Resolution After the America Invents Act,” National Meeting of the American Chemical Society, August 2012
    • “America Invents Act of 2011: How You Can Use It to Your Company’s Advantage,” International Water Conference, November 2011
    • “Effective Use of Patents to Raise Capital and Protect R&D,” Annual Water Innovations Alliance Conference, September 2011
  • Publications
    • “Patenting During the Pandemic,” Thompson Hine COVID-19 Update, April 2020
    • “The U.S. Supreme Court’s Helsinn Decision Makes Six Years of U.S. Patents Vulnerable to “On Sale” Prior Art,” In House Defense Quarterly, Summer 2019
    • “Inventors Beware: Even Secret Activity Can Sink Your Patent,” Thompson Hine Intellectual Property Update, January 2019
    • “Preparing for the Next Generation of Actively Managed ETFs,” Thompson Hine ETF Reg Insights, January 2019
    • “Medical Device Marketing Under Substantial Equivalence – FDA Clearance and USPTO Patent Consideration,” Regulatory Focus, Regulatory Affairs Professional Society, September 2018
    • “Supreme Court Decisions Bring Needed Certainty to PTAB Challenge Process,” Thompson Hine Intellectual Property Update, April 2018
    • “Trump Administration Moves Against Chinese IP Violations,” Thompson Hine International Trade & Intellectual Property Update, August 2017
    • “PTAB Challenges Can Reduce Royalty Obligations, Open New Markets,” Thompson Hine Intellectual Property Update, March 2016
    • “Patent Owner’s Considerations for Review Proceedings at the Patent Trial and Appeal Board (PTAB) Concurrent with Litigation,” IPO White Paper, IPO Law Journal, July 15, 2015 (co-author)
    • “Hague Agreement Enhances Benefits of US Design Patents,” Law360, May 15, 2015
    • “Dollars and Sense: A Water Technology Owner’s Guide to Transferring Intellectual Property,” Ultrapure Water Journal, August 26, 2014
    • “IP Audits: What are they? Why are they important? What do they cost?”, Corporate Compliance Insights, July 15, 2013
    • “Obtaining, Challenging and Enforcing Pharmaceutical Patents Under the America Invents Act,” Pharmaceutical Patent Analyst, September 2012
    • “America Invents Act of 2011: Major Changes in the Law that Will Affect Patent Litigation Strategies,” IP Frontline, October 2011



Washington, D.C.

Clifton McCann


[email protected]




District of Columbia


U.S. Patent and Trademark Office

U.S. Supreme Court

U.S. Court of Appeals for the Federal Circuit

U.S. Court of Appeals for the Fourth Circuit

U.S. Court of Appeals for the District of Columbia Circuit

U.S. District Court for the District of Columbia

U.S. District Court for the Eastern District of Texas

U.S. District Court for the Eastern District of Virginia


George Washington University, LL.M., Intellectual Property, 1985

Catholic University Law School, JD, 1977

Northern Illinois University, B.A., 1972

Prior Law Firm Experience

Venable LLP

Thompson Hine LLP

Practice Areas