Hello there, 

Yes 12th marks matter in NEET.Candidates must have passed 10+2 or equivalent with Physics, Chemistry, Biology/Biotechnology and English as core subjects from a recognized board. Candidates who are appearing for the class 12 or equivalent exam are also eligible to apply for NEET 2020. The marks to be considered are aggregate marks only for PCB subjects :

UR - 50%, 
OBC/SC/ST - 40%, 
PWD - 45%

Hope this helps. 

All the best.!!!

Hello there!, 

Greetings! 

Actually class 12th marks plays a small role in neet as whether you are eligible for neet or not depends on class 12th marks and besides this it doesn't play any role .

The marks  are separate for each category and can be listed as under. The marks to be considered are aggregate marks only for PCB subjects in class XII examination 
UR - 50%, 
OBC/SC/ST - 40%, 
PWD - 45%

To be eligible for Neet,  you need to satisfy above criteria. 

Thankyou