What does it mean by NLPA Notice in Supreme Court ?

Dear Learned Lawyers, Senior Citizen Parents have filed SLP under A136 in SC to Challenge the HC's dismissal of DV quashing petition under 482 crpc & to subsequently Quash of DV complaint against them. In SC; they are the only petitioners & not the son Couple of months back; their matter got finally admitted for detailed hearing after waiting for many years After their matter got admitted; within a week; in SC case status ; I observed that "NLPA" notice issued to the opposite parties. i.e 1) Daughter in law , 2) her private lawyers, 3) State lawyer 4) State Gov. Protection Office 5) SC Registrar etc I need your help understand the meaning of NLPA, what does it do / process and its implication ? Thanks for your help in advance