The question of allowability of amendments is legally a question of whether the application as so amended is allowable. An amended application must of course satisfy all the requirements of the EPC including, in particular, inventive step and the other matters listed in B-XII, 3.6 (see also VI, 3.2). Also, however, especially when the claims have been substantially limited, the examiner should bear in mind that the following questions may require special consideration at the amendment stage:

Do the amended claims still satisfy the requirements of Art. 82? If the search report seems to reveal lack of novelty or inventive step in the concept common to all the claims, but the amended claims do not necessitate further search, the examiner should consider carefully whether an objection of lack of unity is justified at this stage of the proceedings (see III, 7.7). If, however, the claims lack a common inventive concept and a further search is necessary, objection should be raised;

If amended claims are directed to subject-matter which has not been searched (e.g. because it only appeared in the description and the Search Division did not find it appropriate to extend the search to this subject-matter, see B-III, 3.5 ) and which does not combine with the originally claimed and searched invention or group of inventions to form a single general inventive concept, such amendments are not admissible. This applies particularly when this unsearched subject-matter alone is now claimed, whereas it should not be applied if a feature originally disclosed in the description is added to an originally-filed claim in order to meet an objection, e.g. lack of novelty or inventive step, raised by the examiner. In the latter case, however, an additional search (see VI, 8.5 ) may be required;

Thus, if an objection under Rule 86(4) is to be raised, the applicant should be informed that he may continue to pursue such subject-matter only in the form of a divisional application under Art. 76. If no such objection is raised, the Examining Division should consider requesting an additional search (see VI, 8.5 ).

However, applicants should bear in mind that the examining procedure should be brought to a conclusion in as few actions as possible. So the Examining Division may exercise its right not to admit further amendments under Rule 86(3) (see VI, 4.7).

If the claims have been amended, will the description require corresponding amendment to remove serious inconsistency between them? For example, is every embodiment of the invention described still within the scope of one or more claims? (see III, 4.3). Conversely, are all of the amended claims supported by the description? (see III, 6). Also, if the categories of claims have been altered, will the title require corresponding amendment? It is important also to ensure that no amendment adds to the content of the application as filed and thus offends against Art. 123(2), as explained in the following paragraphs.