@sandyshores Retail portion is decided based on type of issue.
1. For Bookbuilding IPO (Profitability route), Retail quota is mimimum 35%
2. For Bookbuilding IPO (QIB route), Retail quota is maximum 10%
3. For Fixed price IPO, Retail quota is minimum 50%
You may find details here :
https://www.chittorgarh.com/book-chapter/ipo-eligibility/3/?#ipo-eligibility-qib-route