Principle
All document transmitted after the filing of the application to an international administration shall:
- accompanied by a letter indicating the international application concerned (R92.1.a PCT).
all letter transmitted after the submission of the application to an international administration must:
- to be signed (R92.1.a PCT).
In case of non-compliance with this requirement a notification is sent to the applicant, giving him a deadline (between 10 days and 1 month) to correct this problem (even if it exceeds the deadline to be met initially, R92.1.b PCT).
Language
RO, ISA, IPEA
Normally letters and documents sent to RO, ISA or IPEA have to be written (R92.2.a PCT):
- in the language of the international application;
- or, as the case may be, in the language of the translation submitted for search, publication or examination.
Letters and documents sent to ISA or IPEA can be written (R92.2.b PCT):
- in any language accepted by this administration.
IB
Letters and documents sent to the IB have to be written (R92.2.d PCT):
- only in English if the international application is in English (together Administrative instructions 104.b),
- only in French if the international application is in French (together Administrative instructions 104.b),
- otherwise, in English or French.
Means of deposit and exchange
Dispatch by the competent administration
By mail
This way is the "classic" way.
If the letter is a delay, it must be sent by air mail exceptR92.3 PCT):
- if mail by land or sea normally arrives within two days,
- if there is no air mail available.
By email
If the competent administration so permits, the letters sent by this administration may also be sent by e-mail (even if only the paper letter is authentic, PCT Newsletter n ° 5/2008).
However, the applicant may indicate that he wishes to receive communications only by e-mail (to the extent that the competent administration accepts it): the response time then starts from the date of dispatch of the e -mail (PCT Newsletter n ° 1/2010 and PCT Newsletter n ° 4/2010).
Sending by the depositor
Mail-in deposit
The applicant may send any mail to the competent administration by post (implicit in the R82.1 PCT).
Filing by fax
Principle
Any document may be sent by fax (or other similar means resulting in a printed or written document, R92.4 PCT) if :
- authorized authority (R92.4.a PCT and R92.4.h PCT) and
- when requested by this administration (possibly in special cases R92.4.f PCT), the original is delivered to the latter within 14 days (R92.4.d PCT).
If the fax is illegible (in whole or in part), the fax is considered as not having been received and the applicant is informed (R92.4.c PCT).
EPO case
It is possible to file any document (except credentials and priority documents) by fax ("Decision of the President of the European Patent Office dated 20 February 2019 concerning the filing of patent applications and other documents by telefax", OJ 2019, A18compliant R92.4.d PCT).
The EPO may invite the applicant to produce a paper confirmation of the documents sent by fax within a 2 months (and not 14 days as indicated above).
If the applicant does not respond to this invitation, the fax is deemed not received.
Electronic filing
Electronic means
Any document may be filed in electronic format (R89bis.2 PCT together R89bis.1.a PCT) if the competent authority accepts this type of deposit (R89bis.2 PCT together R89bis.1.d PCT).
The deposit must then comply with Administrative instructions, chapter 7 and theAnnex F of the Administrative Instructions.
ePCT
This deposit mode allows a deposit via a WEB interface if the RO is the IB (link to the site).
PCT-Easy
The deposit can be made using PCT-EASY : a paper filing accompanied by an electronic version (floppy disk, CD-Rom).
PCT-EASY software can be used (R89ter PCT and R3.1 PCT together Administrative Instructions 102bis.a) if the competent administration accepts it.
The EPO has not accepted a PCT-EASY filing since 1 April 2007 (OG 2007, 58).
PCT-SAFE
WIPO has developed software for online electronic filings (link to the site) at the IB and possibly other RO's accepting it.
Sending by e-mail
It is not possible for the applicant to communicate with an administration by e-mail (PCT Newsletter n ° 4/2009) even to reply to an existing e-mail (eg sent by this administration, see above).
English 
French