NEW YORK--(BUSINESS WIRE)--July 26, 2001--Wolf Haldenstein Adler Freeman & Herz LLP has filed a class action lawsuit in the United States District Court for the Western District of Pennsylvania, on behalf of purchasers of the securities of Marconi PLC (Nasdaq: MONI - news; ``Marconi'' or the ``Company'') between April 11, 2001 and July 4, 2001, inclusive, against defendants Marconi, certain of its officers and directors, and its underwriters. The case name is Prosperitas, Ltd. v. Marconi PLC, et al. A copy of the complaint filed in this action is available from the Court, or can be viewed on the Wolf Haldenstein Adler Freeman & Herz LLP website at http://www.whafh.com The Complaint alleges that defendants violated Sections 10(b) and 20(a) of the Securities Exchange Act of 1934, and Rule 10b-5 promulgated thereunder, by issuing a series of material misrepresentations to the market between April 11, 2001 and July 4, 2001, concerning the demand for its products. Specifically, the complaint alleges that defendants issued several press releases in which they assured investors that the Company would experience an increase in its revenues in the current year and that, despite earnings warnings from most of its competitors, the Company saw no need to change its guidance. On July 4, 2001, however, defendants finally disclosed that they were, in fact, experiencing a slowdown in customer spending and, as a result, the Company expects sales to fall more than 15% and operating profit to fall 50% for the year ending March 2002. The market's reaction to this announcement was immediate and punitive. When shares reopened for trading on July 5, 2001, after having been suspended pending this announcement, the price per share of Marconi American Depositary Receipts dropped by over 50% to close at $3.35 per share, significantly below the Class Period high of $12.50 per share.