Exchange-traded funds or ETFs have become a top target in U.S. regulators' efforts to rein in excessive speculation in oil and other commodity markets, The Wall Street Journal reported on Saturday.

Commodity ETFs, which came into existence in 2003, offer one of the few avenues for small investors to gain direct exposure to commodity markets. The funds pool money from investors to make one-way bets, usually on rising prices.

Some say this causes excessive buying that artificially inflates prices for oil, natural gas and gold.

Commodity ETFs have ballooned to hold $59.3 billion in assets as of July, according to the National Stock Exchange, which tracks ETF data.

The Commodity Futures Trading Commission has said it seeks to protect end users of commodities, and that cutting out individual investors is not the goal.

The Commission has never said, 'You aren't tall enough to ride,' CFTC Commissioner Bart Chilton was quoted as saying in the WSJ article. I don't want to limit liquidity, but above all else, I want to ensure that prices for consumers are fair and that there is no manipulation -- intentional or otherwise.

Limiting the size of ETFs will result in higher costs for investors, the WSJ reported, because legal and operational costs have to be spread out over a fewer number of shares. Investors range from individuals to banks and hedge funds with multimillion-dollar positions.

The CFTC is currently considering a host of measures to curb excessive speculation, including position limits in U.S. futures markets. Many U.S. lawmakers called for greater regulation of some commodity markets after a price surge last year sent crude oil to a record high of $147 a barrel in July 2008.

See also TAKE A LOOK-CFTC takes aim at energy, metals speculation.

(Reporting by Matthew Lewis; Editing by Toni Reinhold)

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