Petro-Logistics is very well connected in the gulf and the Black Sea

From his spare office over a grocery store in Geneva, Conrad Gerber can sway world oil markets. Mr Gerber runs a small firm, Petro-Logistics, that collects and analyses data on the world’s supplies of oil. His confidential reports, which cost his select list of clients as much as $ 5,000 a month, often find their way into the business press, typically causing jumps or dips in the volatile petroleum markets.