Section 12:
Re-opening of assessment at the instance of the assessee.
(1) Where an assessee assessed
under section 11 makes an application to the Income-tax Officer, within one month from the date of
service of a notice of demand issued in consequence of the assessment, for the cancellation of the
assessment on the ground--
(i) that he was prevented by sufficient cause from making the return required under
sub-section (2) of section 8, or
(ii) that he did not receive the notice issued under sub-section (1) of section 10, or
(iii) that he had not a reasonable opportunity to comply, or was prevented by sufficient cause
from complying, with the terms of the notice referred to in clause (ii),
the Income-tax Officer shall, if satisfied about the existence of such ground, cancel the assessment and
proceed to make a fresh assessment in accordance with the provisions of section 10 or section 11.
(2) Every application made under sub-section (1) shall be disposed of within ninety days from the
date of receipt thereof by the Income-tax Officer:
Provided that in computing the period of ninety days aforesaid, any delay in disposing of the
application which is attributable to the assessee shall be excluded.