1. Notice of Opposition  shall be in writing and should be filed together with the affidavit of witnesses and original documents.
2. Prescribed filing fee under the IPO fee structure, which shall be paid upon filing of the opposition/petition for cancellation.
3. Name and address of the opposser/petitioner as well as those of the necessary party or parties respondent.
4. State of the mark, application or registration number, filing date or date of registration of the mark opposed.
5. Name of applicant/registrant.
6. Statutory ground or grounds upon which opposition is sought.
7. Verification.
8. Certification of non-forum shopping.
9. Power of Attorney (POA) granted to the duly authorized representative or agent.
10. Documents executed in foreign country must be legalized and authenticated at least one (1) original exhibit/documentary evidence i.e., affidavit, certificate of registration, sample label, advertisement, etc.

* Certified copies shall be allowed in lieu of the originals.
* Notice of opposition/petition for cancellation must be filed in triplicate one (1) original copy and two (2) duplicate copies.

See Also
Trademark Opposition | Trademark Cancellation | Patent Cancellation