IP/N/l/NGA/T/2 Page 28 Further procedure. Intervention by third parties. 84. Upon such application being made and copy thereof transmitted to the registered proprietor, if necessary, the provisions of regulations 50 to 59 of these Regulations shall apply with the necessary modifications to the further proceedings thereon; but the Registrar shall not rectify the register or remove the mark from the register merely because the registered proprietor has not filed a counter-statement, and in any case of doubt any party may apply to the Registrar for directions. 85. Any person other than the registered proprietor alleging interest in a registered trade mark in respect of which an application is made on Form 27 may apply to the Registrar on Form 28 for leave to intervene, stating thereon the nature of his interest, and the Registrar may refuse or grant such leave, after hearing (if so required) the parties concerned, upon such conditions and terms as he may deem fit. Before dealing in any way with the application for leave to intervene the Registrar may require the applicant to give an undertaking to pay such costs as in the circumstances he may award to any party. Applications for alteration of the Register by correction, change, cancellation or striking out goods, or for entry of disclaimer, memorandum or note (Section 40(1)) 86. An application to the Registrar under section 40(1) of the Act for the alteration of the register by correction, change, cancellation, or striking out goods, or for the entry of a disclaimer or memorandum, may be made by the registered proprietor of the trade mark or by such person as he may satisfy the Registrar that he is entitled to act in the name of the registered proprietor. Such applications shall be made on Forms 19,21, 22, 23, 24, 25 and 33 as may be appropriate; but an application on Form 23 or 24 or 33 shall be signed by the registered proprietor or other person entitled under this Regulation unless in exceptional circumstances the Registrar otherwise allows, or, in the case of Form 33 only, it is signed by an agent expressly authorised for the purpose of such an application. 87. In the case of an application as in the last foregoing Regulation, the Registrar may require such evidence by a statutory declaration or otherwise as he may think fit as to the circumstances in which the application is made. Application under section 40(1). Evidence.