German Court Confirms Validity of Metabolix Patent

Business Wire, June 21, 2007

CAMBRIDGE, Mass. -- Metabolix Inc. (NASDAQ: MBLX), a bioscience company focused on developing clean, sustainable solutions for the world's growing demand for plastics, fuels, and chemicals, today announced that the German Federal Patents Court dismissed in its entirety a patent nullity suit filed by Procter & Gamble Service GmbH. The suit challenged the validity of a patent that is licensed exclusively to Metabolix by the Massachusetts Institute of Technology. On June 14, 2007, the court decided in favor of Metabolix in its defense of the patent, with the plaintiff bearing all costs of the proceeding.

The patent upheld in the suit is the German counterpart of European patent EP 0 482 077, awarded to MIT and licensed exclusively to Metabolix, which covers a method of producing some types of biopolymers. It is the policy of Metabolix to vigorously defend its large portfolio of intellectual property rights worldwide.

About Metabolix

Founded in 1992, Metabolix, Inc. is an innovation driven bioscience company providing clean, sustainable solutions for the world's needs for plastics, fuels, and chemicals. The Company is taking a systems approach, from gene to end product, integrating sophisticated biotechnology with advanced industrial practice. Metabolix is now developing and commercializing Mirel[TM] natural plastics as the sustainable and totally biodegradable alternative to petroleum-based plastics. Metabolix is also developing a proprietary platform technology for co-producing natural plastics, biofuels and chemical products in biomass energy crops such as switchgrass. For more information, please visit www.metabolix.com. (MBLX-G)

Safe Harbor for Forward-Looking Statements

This press release contains forward-looking statements which are made pursuant to the safe harbor provisions of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. The forward-looking statements in this release do not constitute guarantees of future performance. Investors are cautioned that statements in this press release which are not strictly historical statements, including, without limitation, statements regarding the Company's expectations and plans for prosecution and defense of its intellectual property, constitute forward-looking statements. Such forward-looking statements are subject to a number of risks and uncertainties that could cause actual results to differ materially from those anticipated, including, without limitation, the Company's ability to obtain, maintain and protect intellectual property rights for its products, and other risks detailed in Metabolix's filings with the Securities and Exchange Commission, including its Form 10-K for the year ended December 31, 2006. Metabolix assumes no obligation to update any forward-looking information contained in this press release or with respect to the announcements described herein.