Sub-Rules (1) and (2) of Order 3, Rule 4, CPC read as:
(1) No pleader shall act for any person in any Court, unless he has been appointed for the purpose by such person by a document in writing signed by such person or by his recognized agent or by some other person duly authorized by or under a power-of-attorney to make such appointment.
(2) Every such appointment shall be 1[filed in Court and shall, for the purposes of sub-rule (1), be] deemed to be in force until determined with the leave of the Court by a writing signed by the client or the pleader, as the case may be, and filed in Court, or until the client or the pleader dies, or until all proceedings in the suit are ended so far as regards the client.
2[Explanation.-For the purposes of this sub-rule, the following shall be deemed to be proceedings in the suit,-
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So, by mere decision of the suit the contract or appointment of pleader does not come to an end (determined).
CPC does not provide for NOC from previous counsel. However, the relevant rules of the Bar Council prescribe so.