The WIPO Digital Access Service (“DAS”), available at https://www.wipo.int/das/en/, allows you to meet requirements for providing priority and similar documents in respect of participating Offices, without the need to obtain and send multiple certified paper copies of an application.
Instead, you ask the Office where you are claiming priority (“Office of Second Filing” or OSF) to download a copy of the document directly from a digital library, normally held by or on behalf of the Office where the earlier application was filed from which priority is claimed (“Office of First Filing” or OFF).
DAS provides a secure, trusted mechanism which allows Offices both to transmit and to access unpublished documents with confidence that the transmission has been permitted by the applicant or other authorized person.
It is essential that users properly understand what is required to give permission for this transfer. Because the system is designed to work between pairs of Offices, which may have no other working relationship, there are steps involved, which are different from, or additional to those in other priority document exchange systems in operation between certain Offices.
An up-to-date list of participating Offices is maintained on the WIPO DAS website at: https://www.wipo.int/das/en/news
As of November 1, 2025, there are 50 IP Offices participating in WIPO DAS. Other Offices are at various stages of preparation to join the system and are expected to join in the future.
The participating Office’s websites also provide useful DAS information relevant to that particular Office, please see New Office Participation.
The service is intended for use with documents related to patents, utility models, industrial designs and trademarks.
At present, the service is operational for exchange of patent, utility model and design priority documents.
The scope of documents which can be made available also depends on the policy of the Office of First Filing.
Some Offices will allow any patent application filed at their Office to be entered into the system; other Offices offer the service only for a limited range of applications, such as those which have been filed in electronic form.
The relevant scope for each participating Office is outlined on WIPO’s website: https://www.wipo.int/das/en/participating_offices.html
The service will be extended to trademarks once participating Offices have made the necessary changes.
The DAS system depends on the IT systems of many different Offices, over which the International Bureau has no control.
If a library in one Office is temporarily unavailable, requests are queued until systems are restored.
This may cause delays, so it is important to register the application and take the required steps as early as possible.
In extreme cases, the Office of Second Filing may be temporarily unable to retrieve your application, but you should still be given an opportunity to provide a paper certified copy if needed.
If you lose your DAS access code for an earlier application filed at CN, EP, FI, JP, KR, NZ or US, please contact the Office where you filed that application.
If the application was filed at another participating Office, contact the PCT eServices Help Desk for the access code to be resent to the e-mail address you registered for DAS purposes.
The DAS system is the responsibility of the WIPO IP Office Business Division (IPOBSD), working in coordination with the WIPO PCT Sector for questions relating to the IB as an accessing and depositing office.
For more information on legal, operational and technical support: