Benamidar communication for firm registration must be filed in Form No. 12A within prescribed time limits. A partner's communication that another partner is a benamidar, required under the explanation to section 185(1)(b), must be filed in Form No. 12A. The time for making the communication depends on the firm's registration status: if the firm has not been registered under section 184, it must be made before the end of the previous year for the relevant assessment year, subject to the specified transitional allowance; if registration has effect under section 184(7), it must be made before the expiry of the time allowed for furnishing the return of income under section 139.