Filing a Patent Internationally: A Practitioner's Guide to the PCT, the National Stage, and Country Selection
By Casey Scott McKay ·
Foreign filing is usually the largest single expense in a patent portfolio and it is decided under time pressure with incomplete information. This guide runs the decision and the process in fifteen stages, from the disclosure screen that determines whether foreign rights still exist through country selection, the PCT filing, the search report, national phase entry, and prosecution abroad. It explains what the PCT actually buys and what it does not, how to choose between the direct Paris route and the PCT, what drives the cost in each jurisdiction, and how translation and annuity obligations accumulate over a twenty-year term. It covers unity of invention, claim amendment for different offices, and the acceleration mechanisms that exploit work already done. Worked numbers and a decision framework run throughout. The companion article explains the priority chain and the companion checklist tracks the deadlines.
IP and Technology > Patent Counseling Transactions | Guide | Published 15 April 2025 - Updated 18 August 2025 | Casey Scott McKay - marksy.us
Summary. Foreign filing is usually the largest single expense in a patent portfolio and it is decided under time pressure with incomplete information. This guide runs the decision and the process in fifteen stages, from the disclosure screen that determines whether foreign rights still exist through country selection, the PCT filing, the search report, national phase entry, and prosecution abroad. It explains what the PCT actually buys and what it does not, how to choose between the direct Paris route and the PCT, what drives the cost in each jurisdiction, and how translation and annuity obligations accumulate over a twenty-year term. It covers unity of invention, claim amendment for different offices, and the acceleration mechanisms that exploit work already done. Worked numbers and a decision framework run throughout. The companion article explains the priority chain and the companion checklist tracks the deadlines.
Keywords: PCT filing, national stage entry, country selection, Paris Convention, international search report, written opinion, international preliminary examination, foreign filing license, absolute novelty, translation costs, regional patent office, annuities, local counsel, claim amendment, unity of invention, filing strategy, thirty month deadline, twelve month deadline, prosecution highway, portfolio budget
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