Lock-in of promoter securities: minimum holdings non-transferable for prescribed periods, extended where proceeds fund capital expenditure. Specified promoter securities are non-transferable for defined lock-in periods: minimum promoter contribution is locked for eighteen months from IPO allotment (three years where most proceeds fund capital expenditure); excess promoter holdings are locked for six months from allotment (one year where most proceeds fund capital expenditure). 'Capital expenditure' includes civil work, fixed assets, land, building, plant and machinery, and repayment of related loans. SR equity shares remain locked until conversion to ordinary equity with equivalent voting rights or for the applicable promoters' lock-in period, whichever is later.