Inside traders charged over BHP

US federal regulators say two Spanish investors made illegal profits of $US1.1 million ($A1.24 million) by trading on secret information about BHP Billiton PLC's bid to acquire Potash Corp.

The Securities and Exchange Commission Juan Jose Fernandez Garcia and Luis Martin Caro Sanchez bought investments that became valuable after the mining company offered $US38.5 billion ($A43.29 billion) to take over fertiliser maker Potash. Garcia heads the research arm of a bank that was advising BHP on the deal.

The SEC says the pair spent about $US61,000 ($A68,597) this month on contracts that allowed them to buy Potash stock at a set price. It says they knew the price would rise.

BHP last week offered to pay $US130 ($A146) for Potash shares in a hostile attempt to take over the company.