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GenCorp Inc.

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News Release
 
For Immediate Release

GenCorp to Allow Shareholder Rights Plan to Expire

SACRAMENTO, Calif., — March 23, 2006 — GenCorp Inc. (NYSE:GY) today announced that, as part of its ongoing commitment to good corporate governance, GenCorp’s board of directors has unanimously determined to allow the Company’s shareholder rights plan to expire without renewal on February 18, 2007. Furthermore, the board has determined that should the conditions of the rights plan be triggered prior to the scheduled expiration of the rights plan, the Company will either redeem the rights or amend the rights plan to make it inapplicable to such event.

About GenCorp

GenCorp is a leading technology-based manufacturer of aerospace and defense products and systems with a real estate business segment that includes activities related to the development, sale and leasing of the Company’s real estate assets. Additional information about the Company can be obtained by visiting the Company’s web site at http://www.GenCorp.com.

Contact information:

Investors: Yasmin Seyal, senior vice president and chief financial officer 916.351.8585
Media: Linda Cutler, vice president, corporate communications 916.351.8650

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