What is a PCT Application?
One filing, 150-plus countries, and a 30-month clock: the PCT timeline, the international search report, and the national phase decision.
Definition
A PCT application is an international patent application filed under the Patent Cooperation Treaty that preserves the right to seek patents in any of the treaty's 150-plus member states through a single filing. It does not grant an international patent; instead it defers the decision and cost of national filings until 30 or 31 months from the priority date.
Key Facts
- Administered by: The World Intellectual Property Organization (WIPO)
- Members: More than 150 contracting states, including the US, EPO members, China, Japan, and Korea; notable non-members include Taiwan and Argentina
- Filing deadline: Within 12 months of the earliest priority date, typically a provisional or a home-country filing
- National phase deadline: 30 months from the priority date in the US and most offices; 31 months at the EPO and several others
- Result: Separate national or regional applications, each examined under local law
The PCT Timeline
- Month 0: Priority filing
- Month 12: PCT application filed, claiming Paris Convention priority
- Month 16: International search report (ISR) and written opinion on patentability from the chosen International Searching Authority
- Month 18: International publication by WIPO
- Month 22: Deadline to file a Chapter II demand for international preliminary examination, or 3 months from the ISR if later
- Month 28: International preliminary report on patentability, if Chapter II was requested
- Month 30 or 31: National phase entry in each country where protection is wanted
Every milestone is measured from the priority date, not the PCT filing date, which is the most common docketing error in PCT practice.
What the PCT Does and Does Not Do
The PCT centralizes filing, search, publication, and optionally a preliminary examination. It does not grant anything. At the national phase each office applies its own law, charges its own fees, and may demand translations, so a ten-country national phase is often the single most expensive event in a patent family's life.
The ISR and written opinion are the real value. Arriving at month 16, they give the applicant a credible view of patentability before the large national phase spend at month 30, and favorable results can be used to accelerate examination through the Patent Prosecution Highway.
PCT vs Direct Foreign Filing
Filing directly in each country at month 12 is faster to grant and cheaper when only two or three countries are wanted. The PCT wins when the country list is long or undecided, when the applicant needs 18 more months to find licensees or funding, or when an early search opinion would change the filing strategy. ArcPrime's global filing strategy tooling models both paths against the company's markets and competitor footprint so the month 30 decision is made on evidence.
Frequently Asked Questions
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What is the deadline to enter the national phase of a PCT application?
Thirty months from the earliest priority date for the US and most offices. The European Patent Office, Australia, and some others allow 31 months. A few offices permit later entry with a surcharge. The deadline runs from the priority date, not the PCT filing date.
Does a PCT application result in an international patent?
No. There is no international patent. The PCT produces a single international application, search, and publication, after which the applicant must enter the national phase in each country or region where a patent is wanted and be examined under local law.
When must a PCT application be filed?
Within 12 months of the earliest priority filing to claim Paris Convention priority. A PCT application can also be filed first, with no priority claim, in which case the 30-month clock runs from the PCT filing date.
What is the international search report?
A search of prior art by one of the International Searching Authorities, such as the USPTO or EPO, delivered around month 16 together with a written opinion on novelty, inventive step, and industrial applicability. It is not binding on any national office but strongly predicts examination outcomes.
Which countries are not in the PCT?
Notable non-members include Taiwan, Argentina, Venezuela, Pakistan, and Bangladesh. Protection in those countries requires a direct filing within 12 months of priority under the Paris Convention or, for Taiwan, under bilateral arrangements.
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