@K.M.K Ji,
QIB quota consists of Anchor and Non-Anchor investors. They both are institution investors i.e DII, FII etc.
The only differences are they Anchor investors get confirmed allotment one day before opening of IPO and they have lock-in period of 30 & 90 days. The Non-Anchor investors are also QIB who are free to sell on listing day.
Generally IPO quota is segregated as follows:
QIB : 50%/75% ( In which 60% of this 50%/75% is for Anchor investors & rest 40% of this 50%/75% is for Non Anchor Institution investors)
HNI/NII : 15 %( 10% for bHNI , 5% for sHNI)
Retail: 35%/10%.
QIB quota of 75% or 50% on the basis of IPO's company financial & balancesheet as per rules of SEBI.
Hope everything is clear:)