(1) A party requesting a supplementary decision on, or the rectification of, an Award pursuant to Article 49(2) of the Convention shall file the request with the Secretary-General and pay the lodging fee published in the schedule of fees within 45 days after the Award was rendered.
(2) The request referred to in paragraph (1) shall:
(a) identify the Award to which it relates;
(b) be signed by each requesting party or its representative and be dated;
(c) specify:
(i) with respect to a request for a supplementary decision, any question which the Tribunal omitted to decide in the Award;
(ii) with respect to a request for rectification, any clerical, arithmetical or similar error in the Award; and
(d) attach proof of payment of the lodging fee.
(3) Upon receipt of the request and the lodging fee, the Secretary-General shall promptly:
(a) transmit the request to the other party;
(b) register the request, or refuse registration if the request is not filed or the fee is not paid within the time limit referred to in paragraph (1); and
(c) notify the parties of the registration or refusal to register.
(4) As soon as the request is registered, the Secretary-General shall transmit the request and the notice of registration to each member of the Tribunal.
(5) The President of the Tribunal shall determine the procedure to consider the request, after consulting with the other members of the Tribunal and the parties.
(6) Rules 59-60 shall apply to any decision of the Tribunal pursuant to this Rule.
(7) The Tribunal shall issue a decision on the request for supplementary decision or rectification within 60 days after the last submission on the request.
(8) The date of dispatch of certified copies of the supplementary decision or rectification shall be the relevant date for the purposes of calculating the time limits in Articles 51(2) and 52(2) of the Convention.
(9) A supplementary decision or rectification under this Rule shall become part of the Award and shall be reflected on all certified copies of the Award.
-------------
source: https://icsid.worldbank.org/rules-regulations/convention/arbitration-rules/chapter-ix-the-award