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By Douwe Miedema
WASHINGTON, July 30 (Reuters) - The top U.S. securitiesregulator said on Tuesday she was examining insider tradingrules for commodities, further stepping up scrutiny of WallStreet's role in trading anything from oil to metals.
The move comes after JPMorgan Chase & Co - underpressure from regulators - said last week it would exit physicalcommodities trading, and as Europe isdrastically stepping up its rules for commodity trading.
U.S. Securities and Exchange Commission Chair Mary Jo Whitesaid the agency was looking into whether banks should be allowedto own such assets as oil tankers and metal warehouses, whilealso trading in related commodities.
"It's a subject matter that once it came to my attention,and that's fairly recently, I've actually asked the staff toexamine that question, or a series of questions," White told theU.S. Senate Banking Committee in answer to a question by SenatorSherrod Brown.
She also said that "a range of possible disclosures ...could be involved," but gave no further details.
Other large investment banks such as Goldman Sachs Group Inc and Morgan Stanley also have been under intensescrutiny from regulators in recent weeks, with some suspectingthey exert undue influence over commodity markets.
Brown, an Ohio Democrat, has been the most vocal proponentof the view that banks have an unfair advantage in their tradingoperations because they control supply that gives them access tonon-public information.
Last week, big aluminum buyers represented by MillerCoors -America's second-largest brewer - told him and other senatorsthat banks' control of metals warehouses drove up the brewers'costs by as much as $3 billion last year.
Separately, the head of the Senate Agriculture Committeesaid on Tuesday that U.S. futures regulators should reviewalleged manipulation of the aluminum market.
"I am writing to encourage you to further review this issueand clarify the role and responsibility of the Commodity FuturesTrading Commission," Sen. Debbie Stabenow wrote in a letter toGary Gensler, who heads the CFTC.
