Amendment of patent applications is governed by Chapter X of the Act, specifically Sections 57 to 59 of the Act.
Section 57(1) of the Act clarifies that amendment to the complete specification may be undertaken before and after the grant of the patent. What exactly is permitted by way of an amendment is specifically dealt with by Section 59 of the Act.
In understanding this, attention must be paid to Section 59(1) of the Act whose language appears to be circuitous, but on a careful reading reveals its true import. According to Section 59(1), only incorporation of an actual fact by way of a disclaimer, correction or explanation may be permitted in an amendment to the complete specification. Further, the additional conditions that the amendment must satisfy are that:
(1) the amended specification must still be disclosed in substance in the un-amended specification; and
(2) the scope of claims in the amended specification must fall wholly within the scope of the claims of the un-amended specification. The critical point to be noted is that, in understanding the scope of claims in the amended specification, regard must be had to the scope of claims in the originally un-amended specification, and not to the disclosure itself. Therefore, simply put, claims must be compared to claims when an amendment is undertaken in light of their respective specifications.
Both the above listed conditions are conjunctive in nature, and therefore, both must be satisfied by every amendment of the specification undertaken by the patent applicant.
The question that now arises is, do Sections 57 to 59 apply to amendments undertaken by the applicant in response to objections raised in the examination report by the Controller during prosecution of the application? The answer to this lies in Sub-Section 6 of Section 57, which clearly states that the provisions of Section 57 shall be without prejudice to the right of the applicant to amend his specification to comply with the directions of the Controller issued before the grant of a patent.