Shares of oil marketing companies, such as HPCL, BPCL and IOC, may see buying on Tuesday, as they will announce revision of petrol and diesel prices. With crude ruling well below $40 a barrel, there is expectation of bigger price cuts. Besides OMCs, logistics firms, such as Blue Dart, Gati, Snowman, Patel Integrated and VRL, will also benefit. However, shares of upstream oil companies, such as ONGC, Cairn and RIL may come under pressure.