Patrick D. Duplessis

        Partner

        Patrick maintains a diverse IP practice, including patent drafting and prosecution, patent and trademark portfolio management, strategic IP counseling, and litigation. Patrick serves as lead counsel for domestic and international clients of all sizes, from large corporations to venture-backed startups and individuals.

        Patrick has drafted and prosecuted countless patent applications in a wide range of technical fields, including medical devices, aerospace systems, manufacturing tools, analog and digital circuitry, signal processing, software and computer engineering, cybersecurity, and consumer products. He brings a litigation-informed perspective to his patent practice and excels at conveying complex ideas in a simple manner understandable to all.

        Patrick works with clients to develop and implement comprehensive IP strategies that set the stage for capital funding, commercialization, and long-term growth. Patrick conducts freedom-to-operate studies, counsels on product design, and drafts opinions that help his clients assess and manage risks associated with launching new products. He also drafts IP-related agreements and provides day-to-day counseling regarding protection of trademarks, copyright, trade secrets, and other proprietary information.

        Patrick also advocates for clients in litigation and other contested matters related to patents, trademarks, copyrights, false advertising, contracts, privacy, and free speech. Patrick has appeared in U.S. district and appellate courts, and in post-grant proceedings before the Patent Trial and Appeal Board (PTAB) at the U.S. Patent and Trademark Office (USPTO).

        Prior to joining Verrill, Patrick practiced at an IP boutique firm and in the IP group of a large full-service firm. Before graduating law school, he was a law clerk at the Burnham Institute for Medical Research in La Jolla, California, and he held undergraduate research positions at Massachusetts General Hospital and Northwestern University.

        Services/Industries

        Education

        • University of San Diego School of Law (J.D.)
          • Executive Editor, San Diego Law Review
        • Boston University (B.S.)
          • Biomedical Engineering

        Bar Admissions

        • California
        • Connecticut
        • Massachusetts

        Court and Other Admissions

        • U.S. Patent and Trademark Office
        • U.S. District Courts (California, Massachusetts and Connecticut)
        • U.S. Court of Appeals for the Ninth Circuit

        Memberships

        • Judge Janet Bond Arterton American Inn of Court
        • The Federalist Society

        Firm Highlights

        Press Releases

        97 Verrill Attorneys Recognized by Best Lawyers® 2027, Including Four Named Lawyers of the Year

        AUGUSTA, Maine, BANGOR, Maine, BOSTON, Mass., PORTLAND, Maine, and WESTPORT, Conn., (August 20, 2026) – Verrill is proud to announce that 97...
        Alerts and Newsletters

        SEC’s Proposed “Reg Crypto”: What Founders Need to Know

        Startup founders and emerging-growth companies have a number of options for raising capital under the federal securities laws, including Regulation D...
        Blog

        After 45 Years, the IRS Speaks on DCAP Nondiscrimination Testing – And It’s Good News

        Employers that provide a Dependent Care Assistance Program will be pleased to learn that for the first time in 45 years, the IRS has issued guidance...
        Media Mentions

        Robert Keach Discusses Bankruptcy Auction Strategy in Law360

        Verrill attorney Robert Keach spoke with Law360 article examining the complex bankruptcy auction process that resulted in the sale of 23 summer...
        Media Mentions

        Martha Gaythwaite Featured in Portland Press Herald Coverage of Sig Sauer Trial Victory

        Verrill attorney Martha Gaythwaite was highlighted in media coverage of a federal trial in Bangor involving firearm manufacturer Sig Sauer. As...
        Media Mentions

        Law360 Quotes Robert Keach on Senate Bill Affecting Small Business Restructurings

        Verrill attorney Robert Keach was recently quoted in a Law360 article discussing federal legislation that would permanently restore the $7.5 million...
        Alerts and Newsletters

        SAFEs and Preferred Stock – Key Deal Terms Every Founder Should Know

        SAFEs Before negotiating a term sheet for preferred stock, many early-stage companies, particularly at the seed stage, first raise capital through...
        Press Releases

        Verrill Welcomes Business Restructuring and Insolvency Attorney Nimra Tariq

        BOSTON, Massachusetts – Verrill is pleased to announce that Nimra Tariq has joined the firm’s Business Restructuring and Insolvency Group as an...
        Media Mentions

        Robert Keach Provides Commentary on First Brands Restructuring in Law360

        Verrill attorney Robert Keach was quoted in the Law360 article, "First Brands' Ch. 11 Plan Revives Angst Over Admin Claims," discussing First Brands...
        Press Releases

        Verrill Welcomes Construction Attorney Cassie Dufon

        PORTLAND, Maine – Verrill is pleased to welcome Cassie Dufon to the firm’s Construction Group as an Associate, resident in the firm’s Portland...
        Press Releases

        Verrill’s Wide-Ranging Private Wealth Law Practice Recognized in 2026 Chambers and Partners High Net Worth Guide

        BANGOR and PORTLAND, Maine and BOSTON, Mass. – Verrill attorneys Kenneth P. Brier, Anya F. Endsley, Kurt E. Klebe, Mary McQuillen, Nathaniel S....
        Blog

        Update on Status of Maine Packaging EPR

        In December 2024, Verrill published a blog post, Unwrapping Maine's Gift to the Environment: A New Packaging Stewardship Program Set to Launch in...