hello aspirant,

I hope that you are doing absolutely great.

With reference to yoru above mentioned query, i would like to tell you that Yes, you can take part in MOPUP Round counselling in Bihar state only if you have registered yourself in All India Counselling and not as a State Counselling. Other state's students can also take part in mop up round of BiHAR NEET counselling but the only one's who have registered themselves for All India Counselling and not their particular state counselling.

Further, Those candidates who were not allotted seats in round 1 and 2 and those who were out of counselling process for not reporting on their allotted seats were allowed to apply for the mop up counselling round. Besides the ones who have opted for upgradation of seats are eligible to be the part of mop up round.

you can also check out the below link to know more about the Counselling process : https://medicine.careers360.com/articles/neet-counselling

I hope that this will help.