What does RFA OS stands for?

As per your query, RFA OS stands for Regular First Appeal- Original Side.

RFA stands for regular first Appeal. It is provided under Section 96, C.P.C.Section 96 provides that an appeal shall lie from a decree passed by any Court exercising original jurisdiction to the authorized appellate Courts, except where expressly prohibited.

A combined reading of Sections 2(2), 2(9), & 96 of the CPC indicates that a regular First appeal may/may not be maintainable against certain adjudications. 

A regular first appeal may be preferred by one of the following:

• Any party to the suit adversely affected by a decree, or if such party is dead, by his legal representatives under Section 146;
• A transferee of the interest of such party, who so far as such interest is concerned, is bound by the decree, provided his name is entered on the record of the suit;
• An auction purchaser may appeal against an order in execution setting aside the sale on the ground of fraud;
• No other person, unless he is a party to the suit, is entitled to appeal under Section 96.

A person, who is not a party to the suit, may prefer an appeal from a decree/order if he’s bound/aggrieved/prejudicially affected by it via special leave of the appellate Court. 

Hope this helps

Regards

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