Oil-Logistics

Oilgaztreyd

Oils and Lubricants

Oiltron Refinery

Okunevskoye Refinery

Omsk Oil Refinery

Opet.Ru

Optima Neftegaz

Orda Sintez Gaz

Orenburgneftegaz

Orenneft

Orlovsky Refinery

Orsknefteorgsintez

Otchizna

Oylgaztet

Ozenmunaygas

Paiga

Pallas

Oil-Petroleum Ns

Oilnavigator

Oiltek Consultant Company

Okhtin-Oils

Omega

Oparinskoe

Ophergasneft

Oraltek-Neftehim

Orenburgneft

Orenburgnefteotdacha

Orlan Servis

Ornako

Oskar Oil Company

Otradnenskiy Refinery

Oylinvest

Pacific Petroleum

Pak Oil

Panelskaya Ngk