Shares of oil marketing companies such as BPCL, HPCL and Indian Oil and upstream company ONGC could come under pressure at the bourses as Brent crude prices jumped more than $2 to over $112 a barrel on Thursday. Analysts worry that escalating violence in Iraq could disrupt oil supplies from the major OPEC exporter. For these companies, rising crude prices could increase the subsidy burden, which has remained relatively stable for some time now on rising rupee and stable crude prices.