Cut-off date for Patent Invalidation. Related to patent invalidity. Patents and intellectual property topic. How a date criteria set when we conduct or see the prior art for invalidating a patent or patent in question? Criteria for the cutoff date may vary as per the jurisdiction. It helps to start a good search strategy.

1. Prabhat Saini
Cut-off date
for patent invalidation
1

2. Place your
table,
chart or
scheme
here
Invalidity search is
an extensive
and date-restricted
prior art search.
The cut-off date
is crucial
to invalidate
a patent.
It is conducted against the claims of a
patent to render them invalid by revealing
pertinent prior art filed before the Patent’s
earliest priority date.
It is done to defend against a claim
of patent infringement in court or
to challenge a patent using pre- or post-
grant opposition options.
Invalidity search: Cut-off date Jurisdiction
wise
China
Date of filing (DOF) or date of priority (DOP) of a patent,
whichever is earlier
Japan Date of publication of the prior art document with
respect to the filing date or the priority date of the
subject patent.
• In case, when a secret prior art is considered for
invalidation, then the DOF or DOP of said secret prior
is checked with the DOF or DOP of the subject patent
India Usually, before the date of filing of the subject patent.
• If a relevant prior art is published after the DOF of the
subject patent, however, the DOF or DOP is before the
DOF or DOP of the subject patent, then it is considered
as relevant prior art
2
….continued
Cut-off or critical date represents the date of
filing or priority of a subject patent in question.

3. Place your
table,
chart or
scheme
here
Cut-off date: jurisdiction wise
3
Europe 1. If an application claims any right of priority then the date of filing or
DOF of the previous application becomes the cut-off date
2. If the application does not claim any right of priority then the date of
filing or DOF of the application becomes the cut-off date.
Korea The date of filing or DOF of the application or ;
In the case of an application with a priority claim, then the date of priority
or DOP.
Australia Documents published before the date of priority or DOP of the subject
patent or the date of the first patent application.

4. First Scenario: Foreign patent/ published
application or priority from foreign patent/
published application
Pre-AIA: Cut-off date- publication date
or grant date, whichever is earlier.
Second Scenario: International application or
priority from International application
Filed before November 29, 2000:
the publication date is considered
as the cut-off date,
For US applications claiming priority
from the international application-
filing date of the US patent/application
USA
4
For US patent/published application
claiming priority from said foreign
patent/published application- cut off
date is DOF of the US patent/
published application
Post-AIA: cut-off date is DOF of the
Foreign patent/ published application,
provided certain conditions.
US applications published directly
from the international application- the
publication date of the US application
is considered as the cut-off date
……….continued

5. Filed on or after November 29, 2000:
If the PCT application is published
in English designating the US- then
the PCT filing date or earlier filing date,
considering the priority claimed
If the US patent/published application
claiming priority from such application
and is not published in English- the DOF
of said US patent/published application
Third Scenario: US only
For Continuation or divisional- the earliest
filing date of the US application
For the CIP of an earlier US application- subject
matter not disclosed in earlier application- then
the filing date of CIP
If the subject matter is disclosed in the earlier-
filing date of said parent or earlier patent
application
USA
5
When a non-provisional application is filed
post-provisional application, then the DOF of
the provisional application is the cut-off
date, provided the subject matter is
completely disclosed in the provisional
application

6. THANK
YOU
6 Flag(s) are used herein just for
educational purposes.