* Investigators at Platts in London for third day
* Raid the price of being relevant, Platts boss told staff
* Platts vetting procedure for price contributions in focus
* Platts still operating business as usual
By Peg Mackey
LONDON, May 16 (Reuters) - European anti-trust investigatorssearched the offices of price agency Platts and at least onemajor oil company for a third day on Thursday, hunting forevidence of possible price manipulation on oil markets,witnesses said.
Authorities raided the London bureau of Platts in CanaryWharf and the offices of Statoil, Royal Dutch Shell and BP on Tuesday in the biggest trading probesince the Libor scandal.
At issue is whether there was collusion to distort prices ofcrude, refined oil products and ethanol traded during the Plattsmarket-on-close (MOC) system - a daily half-hour "window" inwhich it sets prices.
With attention focused on the role of Platts in setting oilprice benchmarks, the publisher - a unit of McGraw-Hill - is in lockdown during the European Commission's inspection,say sources familiar with the company.
A team of inspectors is gathering evidence from laptops, thewitnesses said.
"We are all in the dark about it. The investigators willlikely be here all week," said one member of Platts staff. "We have all been told explicitly not to speak to anyone aboutit."
Platts continues to operate business as normal, traderssaid.
As investigators raided the office, reporters were told byPlatts management to cooperate. Editorial director Dan Tanzstood up to say it was the "price of being relevant".
A spokeswoman for Platts did not immediately respond to arequest for comment.
Britain's Serious Fraud Office said it had not yet decidedwhether to "accept this matter as a criminal investigation".
"Subject to discussions with other agencies, it is likelythat the SFO could be the appropriate authority to investigateallegations of price fixing," the SFO said in a statement.
The European Commission also is examining whether companieswere prevented from taking part in the price assessment process.
A Hungarian ethanol producer on Wednesday was the firstcompany to identify itself as having complained to the EuropeanCommission about a Platts procedure that vets companies beforethey are permitted to participate in its price settingmechanism.
Pannonia Ethanol said it approached Platts last spring togain access to contribute to the market-on-close window.
It said Platts refused to give the company access, citing"editorial discretion".
Platts said its established procedure was to vet newparticipants and had followed the process with Pannonia Ethanol.
Commission inspectors are also continuing their search atthe offices of Norwegian Statoil.
"As far as I know, the inspectors are still at our office,"said Statoil spokesman Jannik Lindbaek. "When they came theysaid that they would spend some days."
BP and Shell said they were still cooperating with theEuropean authorities.
London is home to some of the biggest trading desks in theoil business. Following the Libor scandal, in which banks haveadmitted trying to manipulate interest rates, Britain approvedlegislation making a criminal offence of false or misleadingstatements in relation to the setting of financial benchmarks.
Britain would be unable to use that law to act against anyoil companies found guilty of price manipulation because the lawdoes not include energy benchmarks and punishment would not bedoled out retrospectively, the prime minister's office said onThursday.
That leaves the European Commission, which can impose largefines, as the most likely source of any sanctions.
Thomson Reuters, parent of Reuters news, competeswith Platts in providing news and information to the oil market.