Hedge funds and speculators reduced positions in oil by 80% as prices rose to records and as U.S. regulators started investigating trading, Bloomberg News reported Monday, citing government data.

Net long positions decline to 25,867 contracts on the New York Mercantile Exchange in the week ended May 27, 2008 from a record 127,491 contracts on July 31, 2008 according to a U.S. Commodity Futures Trading Commission report.

Last week, the CFTC, under pressure from Congress, announced that it had expanded an investigation of oil's price rise and oil futures contracts. Oil has increased about 100% in the past 12 months, and about 480% since 2002. Oil rose $1.50 to $128.50 per barrel in mid-day Monday trading.

U.S. regulators Friday disclosed a broad nationwide investigation into potential oil-market manipulation and said they are expanding surveillance of energy markets, The Wall Street Journal reported Friday.

The Commodity Futures Trading Commission announcement of an ongoing and widening inquiry occurs amid a 4-year rise in crude oil prices in which gasoline, diesel, and heating oil prices hit record highs, Reuters reported Friday.

Oil closed Friday up 73 cents to $127.35 per barrel. Oil has risen about 100% in the past 12 months.

Many Congressional officials and consumer groups have been arguing for a systematic investigation into futures prices, asserting that institutional investors and other speculators have manipulated oil prices and driven them "artificially higher."

Others, including economists and oil executives, argue that the price increases have more to do with the sector's bullish fundamentals, including inadequate crude oil production growth amid rising demand.

Oil Analysis: Strong evidence suggests that the bulk of oil's 4-year bullish run is rooted in fundamentals, with the reduction in the global safety cushion -- the spare oil between daily global oil supply and demand -- accounting for today's near-record oil prices. Still, that's not to say a rigorous inquiry would not yield compelling data or new insights. One area of interest that the inquiry will explore: whether oil storage operators have issued misleading information about oil in their tanks to profit from oil trades, Reuters reported Friday.

The commodities fad took a major step toward becoming an investment trend when investment giant Calpers -- the $240 billion California Public Employees' Retirement System -- announced it may increase its commodities investments 16-fold to $7.2 billion through 2010, Bloomberg News reported Thursday.

Calpers, the largest pension fund in the United States, said it would hold between 0.5% and 3% of its assets in commodities. Last year the fund invested $450 million in commodities.

Strong emerging market growth, particularly in China and in sections of Latin America, has created a bull market in oil, commodities and raw materials, and many economists say these assets are likely to outperform both inflation and selected investment classes in 2008, and possibly for a longer time period.

The Standard & Poor's GSCI index of 24 commodities is up 10% so far in 2008, following a 33% gain in 2007. Meanwhile, the Standard & Poor's 500 Index of stocks is down 6% this year, while U.S. Treasuries have netted a 2% return.

Everything's big in Texas. Look at the state's Teacher Retirement System (TRS). In all, it has about $112 billion in assets.

Interestingly enough, the pension fund wants to devote about a third of its assets to alternatives, such as hedge funds and private equity funds. This is according to a story in the Wall Street Journal [a paid service].

Yes, when you take a look a the SEC filings of the Blackstone Group (NYSE: BX), Fortress (NYSE: FIG), and KKR, you will see that alternative investment can post strong returns.

Despite this, the TRS strategy is certainly gutsy. Keep in mind that alternative investments can be fairly illiquid. What if it gets tougher to do IPOs or get sound exits on these investments?

Or, what if there is a meltdown, as seen with the subprime hedge funds at Bear Stearns (NYSE: BSC)?

Even the pros can make big blunders. And it could be bad news for pensioners.

On the other hand, TRS's move is certainly good news for the private equity world. Simply put, there's likely to be many more assets under management -- and that means lots of juicy fees.

Tom Taulli is the author of various books, including the Complete M&A Handbook and the EDGAR-Online Guide to Decoding Financial Statements.