It's no longer just

Citigroup

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that's on the congressional hot seat when it comes to the subject of initial public offerings.

Late Wednesday, the House Financial Services Committee announced it is expanding its investigation into some of Wall Street's business practices to include

Credit Suisse First Boston

and

Goldman Sachs

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-- two of the biggest IPO underwriters during the bull market.

Rep. Michael Oxley (R., Ohio), the committee's chairman, sent letters to each investment bank seeking information about their policies and procedures for doling out shares in hot IPOs to corporate executives, and on dealing with analyst conflicts of interest. In particular, the committee is seeking information about any IPO shares that may have been allocated by the firms to executives and officers of

TheStreet Recommends

Enron

and

Global Crossing

.

The broadening of the committee's inquiry comes a week after Citigroup disclosed that its Salomon Smith Barney investment banking arm allocated thousands of shares of hot IPOs to corporate executives, including former WorldCom Chairman Bernard Ebbers. The documents provided to the committee by Salomon revealed that Ebbers netted $11 million on those IPO shares.

In the days since Citi provided the IPO information to the committee, there has been a growing cry on Capitol Hill for a more expansive look into how Wall Street conducted business during the bull market. Some said it made little sense for Congress to single out Citigroup, because it was a widespread practice on Wall Street for investment banks to dole out IPO shares to corporate executives.

"Insider allocation of initial public offering shares unfairly dilutes the value of the stock for the small investor," said Oxley, in a prepared statement.

It's not surprising that the committee would expand its investigation by focusing on CSFB and Goldman. Both firms were leaders in underwriting IPOs for technology and Internet companies -- the kind of new issues investors clamored for during the bull market. Indeed, the issue of IPO allocations has dogged CSFB for some time. Last winter it paid a $100 million fine to the Justice Department to settle charges that the firm had demanded inflated commissions from money managers who were seeking to buy shares in some hot technology IPOs.

In fact, according to Equidesk, a Wall Street research firm, both Goldman and CSFB scored near the top of the charts when it came to underwriting IPOs that generated the best first-day price gains. Of the 100 IPOs with the best opening-day performances from 1997 through 2001, Goldman was the lead underwriter on 20 of them, while CSFB served as the lead banker on another 17 deals.

By comparison, just three of Salomon's IPOs cracked the list of the 100 best-performing first-day IPOs.

It's also no surprise that the committee wants to look at both firms with regard to any IPO shares they may have doled out to Enron executives. In the 1990s, Goldman was one of Enron's principal merger-and-acquisition advisers. And CSFB, according to Thomson Financial Securities Data, served as the underwriter on more public stock and bond offerings for Enron than any other Wall Street investment bank.

The committee has given both investment firms until Sept. 19 to comply with the request.