The international application shall not contain:

1. (i) expressions or drawings contrary to morality;
2. (ii) expressions or drawings contrary to public order;
3. (iii) statements disparaging the products or processes of any particular person other than the applicant, or the merits or validity of applications or patents of any such person (mere comparisons with the prior art shall not be considered disparaging per se);
4. (iv) any statement or other matter obviously irrelevant or unnecessary under the circumstances.

The receiving Office, the International Searching Authority, the Authority specified for supplementary search and the International Bureau may note lack of compliance with the prescriptions of Rule 9.1 and may suggest to the applicant that he voluntarily correct his international application accordingly, in which case the receiving Office, the competent International Searching Authority, the competent Authority specified for supplementary search and the International Bureau, as applicable, shall be informed of the suggestion.

"Disparaging statements," referred to in Article 21(6), shall have the meaning as defined in Rule 9.1(iii).