Section 11 – THE PATENTS ACT, 1970

—(1) There shall be a priority date for
each claim of a complete specification.
(2) Where a complete specification is filed in pursuance of a single application accompanied
by—
(a) a provisional specification; or
(b) a specification which is treated by virtue of a direction under subsection (3) of
section 9 as a provisional specification,
and the claim is fairly based on the matter disclosed in the specification referred to in
clause (a) or clause (b), the priority date of that claim shall be the date of the filing of the
relevant specification.
(3) Where the complete specification is filed or proceeded with in pursuance of two or more
applications accompanied by such specifications as are mentioned in sub-section (2) and
the claim is fairly based on the matter disclosed—
(a) in one of those specifications, the priority date of that claim shall be the date of the
filing of the application accompanied by that specification;
(b) partly in one and partly in another, the priority date of that claim shall be the date
of the filing of the application accompanied by the specification of the later date.
(3A) Where a complete specification based on a previously filed application in India has been
filed within twelve months from the date of that application and the claim is fairly based
on the matter disclosed in the previously filed application, the priority date of that claim
shall be the date of the previously filed application in which the matter was first disclosed.
(4) Where the complete specification has been filed in pursuance of a further application made
by virtue of sub-section (1) of section 16 and the claim is fairly based on the matter
disclosed in any of the earlier specifications, provisional or complete, as the case may be,
the priority date of that claim shall be the date of the filing of that specification in which the
THE PATENTS ACT, 1970
Page 15
matter was first disclosed.
(5) Where, under the foregoing provisions of this section, any claim of a complete specification
would, but for the provisions of this sub-section, have two or more priority dates, the
priority date of that claim shall be the earlier or earliest of those dates.
(6) In any case to which sub-sections (2), (3), (3A), (4) and (5) do not apply, the priority date of a
claim shall, subject to the provisions of section 137, be the date of filing of the complete
specification.
(7)The reference to the date of the filing of the application or of the complete specification in
this section shall, in cases where there has been a post-dating under section 9 or section 17
or, as the case may be, an ante-dating under section 16, be a reference to the date as so
post-dated or ante-dated.
(8)A claim in a complete specification of a patent shall not be invalid by reason only of—
(a) the publication or use of the invention so far as claimed in that claim on or after the
priority date of such claim; or
(b) the grant of another patent which claims the invention, so far as
claimed in the first mentioned claim, in a claim of the same or a later priority date.