(For rejection of the opposition as inadmissible at a later stage, the patent proprietor being a party, see D‑IV, 5.1 and D-IV, 5.5)

In cases of insufficient substantiation, where the formalities officer is not competent to decide on the inadmissibility (see D‑IV, 1.2.2.1(v)), the opposition division will either:

If the opponent does not refute the opinion expressed by the opposition division on the existence of these deficiencies which may no longer be corrected, the opposition division will reject the notice of opposition as inadmissible, possibly after having held oral proceedings. As regards the form of the decision, see E‑X, 2.3, and E‑X, 2.6.

The decision will be communicated to the other parties. An inadmissible opposition or documents produced in support of an inadmissible opposition will be placed in the file and will therefore be available for inspection in accordance with Art. 128(4). As regards the possibility of taking them into consideration as observations by third parties, see D‑V, 2.2, and E‑VI, 3. If there are further admissible oppositions, for reasons of procedural economy this decision to reject the opposition as inadmissible will normally be taken at the end of the procedure together with the decision on the admissible oppositions.

For the possibility of appeal by the opponent and other possible means of redress, see E‑XII, 1, and E‑XII, 7.