International
The PCT Timeline
A US patent protects you only in the US. To protect an invention internationally, the Patent Cooperation Treaty is the most common route — not because it grants a global patent (no such thing exists), but because it buys you time and a unified filing. Here is the timeline.
Educational guide, not legal advice. International filing strategy should be set with a patent attorney.
First, the big misconception
The PCT is not a world patent. There is no such thing. Patents are territorial — every country grants and enforces its own. The PCT is a unified filing + search + delay mechanism that preserves your right to pursue patents in 150+ countries, while postponing the expensive country-by-country decision to month 30.
- Month 0
Priority filing
You file your first application (often a US provisional or non-provisional). This sets your priority date — the date that counts for novelty everywhere. The clock for everything else starts here.
- By month 12
File the PCT application
Under the Paris Convention, you have 12 months from your priority date to file abroad while keeping the priority date. Filing a single PCT application by month 12 preserves your rights in all 150+ PCT contracting states at once — instead of filing separately in each country now.
- ~Month 16
International Search Report (ISR) + Written Opinion
An International Searching Authority conducts a prior-art search and issues the ISR plus a non-binding Written Opinion on novelty, inventive step, and industrial applicability. This is a valuable early read on your invention's patentability — before you spend on national filings.
- Month 18
International publication
WIPO publishes your application. It becomes public worldwide (and counts as prior art against others). If you needed secrecy, this is the point it ends.
- Optional, ~month 22
Chapter II: International Preliminary Examination
Optionally, you can request a fuller preliminary examination (and amend claims) to get a more developed opinion on patentability before national phase. Useful when the initial Written Opinion was unfavorable and you want to strengthen your position.
- By month 30 (the big one)
National / regional phase entry
The critical deadline. By 30 months from priority, you must enter the national or regional phase in each jurisdiction where you want a patent — filing with each office (USPTO, EPO, JPO, CNIPA, etc.), paying their fees, and providing translations. This is where the real cost lands. Each office then examines and grants (or refuses) its own patent independently.
Why bother with the PCT?
The alternative to the PCT is filing directly in each country within the 12-month Paris Convention deadline — committing to all that translation and filing cost up front, before you know which markets matter. The PCT pushes that decision out to 30 months.
That extra ~18 months is the whole point. It buys time to gauge commercial traction, raise money, and see the International Search Report before committing to expensive national filings — and it gives you a single, unified application to manage in the meantime. The trade-off is added PCT fees and an extra procedural layer.
For a startup unsure which countries will matter, the PCT is usually the right call. For an inventor certain they only want protection in one or two specific countries, filing directly in those countries can be cheaper.