over-allotment
noun[CorU]
(alsooverallotment)ukusFINANCE,STOCK MARKET
in ashareoffering(=timewhensharesareofferedforsale),extrasharesthat areavailableif all themainsharesaresold:
AT&T made anofferingof 4.2 millioncommonshareswith anoverallotmentoptionof 630,000shares.