Chapter 1800

Patent Cooperation Treaty

Chapter 1800 covers the Patent Cooperation Treaty (PCT) process. Key timeline: file PCT within 12 months of priority, publication at 18 months, Chapter II demand by 22 months, national phase entry by 30 months from priority date — all running from PRIORITY DATE not PCT filing date.

Core Concepts

PCT Filing — MPEP 1801 File PCT application within 12 months of first priority filing. Designates multiple countries in one filing. Receiving Office (RO) processes PCT application. USPTO acts as Receiving Office for US applicants. PCT application must be in PCT language (English for USPTO).

International Search — MPEP 1843 International Searching Authority (ISA) conducts search and issues International Search Report (ISR) and Written Opinion. ISR cites prior art. Written Opinion is preliminary examination opinion. IPRP (International Preliminary Report on Patentability) issued at end of Chapter I or Chapter II.

PCT Timeline — Critical Deadlines 12 months from priority: PCT filing deadline. 18 months from priority: international publication (automatic). 22 months from priority: Chapter II demand deadline to extend examination. 30 months from priority: national phase entry deadline (most countries). All deadlines run from PRIORITY DATE.

Chapter II Demand — MPEP 1864 Optional request for International Preliminary Examination (IPEA). Must file by 22 months from priority. Extends national phase entry in Chapter II countries. IPRP Chapter II issued after international preliminary examination.

National Phase Entry — MPEP 1893 Enter national phase by 30 months from priority date. Must pay national fees and file translations. Missing 30-month deadline: most countries allow late entry with fee and excuse. US national phase: file under 35 USC 371. Can also bypass PCT and file directly under 35 USC 111(a).

Unity of Invention — MPEP 1850 PCT standard: single general inventive concept. More permissive than US restriction practice. Lack of unity in international phase does not bind national phase examination. USPTO may require restriction after national phase entry.

Key Rules

1.All PCT deadlines run from PRIORITY DATE — not PCT filing date

2.National phase entry: 30 months from priority date

3.Chapter II demand: 22 months from priority date

4.International publication: 18 months from priority — automatic

5.ISA issues International Search Report and Written Opinion

6.Lack of unity in international phase does not bind US national stage

7.US national phase entry under 35 USC 371 requires fee and translation

EXAM TIP

PCT timeline is the most tested area — all deadlines run from the PRIORITY DATE of the earliest application, not the PCT filing date. The exam will give scenarios with multiple dates — always calculate from the priority date: 18 months (publication), 22 months (Chapter II demand), 30 months (national phase).

Common Traps

1.Calculating PCT deadlines from PCT filing date instead of priority date

2.Missing that 18-month publication is automatic — no action needed

3.Thinking Chapter II demand is required — it is optional

4.Assuming lack of unity in PCT binds US national stage — it does not

5.Confusing 35 USC 371 (PCT national stage) with 35 USC 111(a) (bypass continuation)

Search Terms

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Sections

1801Basic Patent Cooperation Treaty (PCT) Principles

High Yield

1802PCT Definitions

1803Reservations Under the PCT Taken by, and Notifications of Incompatibility Made by, the United States of America

1805Where To File an International Application

1806Applicants and Inventors

1807Agent or Common Representative and General Power of Attorney

1808Change in or Revocation of the Appointment of an Agent or a Common Representative

1809Access to the USPTO patent electronic filing system

1810Filing Date Requirements

1812Elements of the International Application

High Yield

1817PCT Member States

1819Earlier Search

1820Signature of Applicant

1821The Request

High Yield

1823The Description

1824The Claims

1825The Drawings

1826The Abstract

1827Fees

1828Priority Claim and Document

High Yield

1830International Application Transmittal Letter

1832License Request for Foreign Filing Under the PCT

1834Correspondence

1836Rectification of Obvious Mistakes

1840The International Searching Authority

1842Basic Flow Under the PCT

1843The International Search

1844The International Search Report

1845Written Opinion of the International Searching Authority

1848Sequence Listings

1850Unity of Invention Before the International Searching Authority

1851Identification of Patent Documents

1852Taking Into Account Results of Earlier Search(es)

1853Amendment Under PCT Article 19

High Yield

1856Supplementary International Searches

1857International Publication

1859Withdrawal of International Application, Designations, or Priority Claims

1860International Preliminary Examination Procedure

1862Agreement With the International Bureau To Serve as an International Preliminary Examining Authority

1864The Demand and Preparation for Filing of Demand

High Yield

1865Filing of Demand

1867Preliminary Examination Fees

1868Correction of Defects in the Demand

1869Notification to International Bureau of Demand

1870Priority Document and Translation Thereof

1871Processing Amendments Filed Under Article 19 and Article 34 Prior to or at the Start of International Preliminary Examination

1872Availability of the International Application File for International Preliminary Examination by the Examining Corps

1874Determination if International Preliminary Examination Is Required and Possible

1875Unity of Invention Before the International Preliminary Examining Authority

High Yield

1876Notation of Errors and Informalities by the Examiner

1877Nucleotide and/or Amino Acid Sequence Listings During the International Preliminary Examination

1878Preparation of the Written Opinion of the International Preliminary Examining Authority

1879Preparation of the International Preliminary Examination Report

1880Withdrawal of Demand or Election

1881Receipt of Notice of Election and Preliminary Examination Report by the United States Patent and Trademark Office

1893National Stage (U.S. National Application Filed Under 35 U.S.C. 371)

High Yield

1895A Continuation, Divisional, or Continuation- in- Part Application of a PCT Application Designating the United States

1896The Differences Between a National Application Filed Under 35 U.S.C. 111(a) and a National Stage Application Submitted Under 35 U.S.C. 371