Hello aspirant,
The maximum qualifying percentile signifies the least percentile required to qualify NEET 2019. Since the percentile depends on the the relative performance of all the candidates who have appeared for the exam, the corresponding marks can only be seated the maximum percentile is that

• For unreserved - 50percentail
• For SC /ST/OBC/SC-PH/ST-PH/OBC-PH is 40 percentile

If you have any questions please let me know
All the best!!
Thank you!!!