8-K

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SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 8-K

Current Report

Pursuant to Section 13 or 15(d) of the Securities
Exchange Act of 1934

June 9, 2003
Date of Report (Date of earliest event reported)

INVESTMENT TECHNOLOGY GROUP, INC.
(Exact name of registrant as specified in its charter)

Delaware
(State or other jurisdiction of
incorporation or organization) 0-23644
(Commission file number) 95-2848406
(I.R.S. Employer Identification No.)

380 Madison Avenue
New York, New York 10017
Address of principal executive offices)

(212) 588-4000
(Registrant's telephone number, including area code)

Not Applicable
(Former name or former address, if changed since last report)

Item 5.    Other Events

        On June 9, 2003, Investment Technology Group, Inc. issued a press release announcing trading statistics for the month ended May 30, 2003. A copy of this press release is attached hereto as Exhibit 99.1.

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SIGNATURE

        Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	INVESTMENT TECHNOLOGY GROUP, INC.
	(Registrant)
Date: June 9, 2003	By:	/s/  HOWARD C. NAPHTALI Howard C. Naphtali Chief Financial Officer and Duly Authorized Signatory of Registrant

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EXHIBIT INDEX

Exhibit No.	Description
99.1	Press Release by Investment Technology Group, Inc., dated as of June 9, 2003

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SIGNATURE
EXHIBIT INDEX

EX-99.1

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Exhibit 99.1

ITG Releases May 2003 Trading Statistics

NEW YORK, NY, June 9, 2003—Investment Technology Group, Inc. ("ITG") (NYSE: ITG) today announced that U.S. trading volume was 2.2 billion shares for the month ended May 30, 2003, averaging 94 million shares per day. This compares to 1.2 billion shares (62 million per day) in April 2003 and 2.2 billion shares (91 million per day) in May 2002.

        For the month ended May 30, 2003, U.S. trading volumes were 747 million shares for POSIT®, 972 million shares for Client-Site Trading Products, and 529 million shares for the Electronic Trading Desk. This data excludes all operations outside the United States and excludes statistics for Hoenig & Co., Inc., which ITG acquired on September 3, 2002. There were 24 trading days in May 2003, compared to 19 trading days in April 2003 and 24 trading days in May 2002.

        Monthly volume statistics are preliminary and, accordingly, may be revised in subsequent updates and public filings. Volume statistics are posted on ITG's web site, http://www.itginc.com, and are also available via a downloadable spreadsheet file.

ITG U.S. Trading Activity

Total U.S. Shares	# of Trade Days	POSIT	Client Site Trading Products	Electronic Trading Desk	Total U.S. Volume	Average U.S. Daily Volume
May:	24	746,865,168	971,793,096	529,278,766	2,247,937,030	93,664,043
Year-to-Date:	103	2,359,464,253	3,709,509,768	1,614,427,434	7,683,401,455	74,596,131

        —more-

Boston    •    Dublin    •    Hong Kong    •    London     •    Los Angeles    •    Melbourne    •    New York    •     Sydney    •    Tel Aviv    •    Toronto

ITG Releases May 2003 Trading Statistics Page 2

About ITG

        ITG is headquartered in New York with offices in Boston, Los Angeles, Dublin, Hong Kong, London, Melbourne, Sydney, Tel Aviv and Toronto. As a leading provider of technology-based equity-trading services and transaction research to institutional investors and brokers, ITG's services help clients to access liquidity, execute trades more efficiently, and make better trading decisions. ITG generates superior trading results for its clients through three lines of business. POSIT®, the world's largest equity matching system, allows clients to trade confidentially. The Electronic Trading Desk is recognized as one of the leading program trading operations in the U.S. ITG's leading-edge Client Site Trading Products allow users to implement their own trading strategies by providing direct electronic access to most sources of market liquidity. For additional information, visit http://www.itginc.com.

In addition to historical information, this press release may contain "forward-looking" statements, as defined in the Private Securities Litigation Reform Act of 1995, that reflect management's expectations for the future. A variety of important factors could cause results to differ materially from such statements. These factors include the company's ability to achieve expected future levels of sales; the actions of both current and potential new competitors; rapid changes in technology; financial market volatility; general economic conditions in the United States and elsewhere; evolving industry regulation; cash flows into or redemption from equity funds; effects of inflation; customer trading patterns; and new products and services. These and other risks are described in greater detail in the company's Annual Report on Form 10-K for the fiscal year ended December 31, 2002 and other documents filed with the Securities and Exchange Commission and available on the company's web site.

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ITG Releases May 2003 Trading Statistics