Investor Relations

PRESS RELEASE November 4, 2004
Marcia Miller, Director of Marketing
Metabolix, Inc., 21 Erie St.
Cambridge, MA 02139
617-492-0505 x227; fax: 617-492-1996
miller@metabolix.com

November 4, 2004, Cambridge, MA- Metabolix, Inc. and Archer Daniels Midland Company (ADM) announced today that they have entered a strategic alliance with the purpose of commercializing a new generation of high-performance natural plastics that are eco-friendly and based on sustainable, renewable resources. Through the alliance, the two companies are planning to establish a state-of-the-art 50,000-ton production facility and a 50/50 joint venture to manufacture and market natural PHA polymers for a wide variety of applications, including coated paper, film, and molded goods. Natural PHA polymers are produced using a fully biological fermentation process that converts agricultural raw materials such as corn sugar into a versatile range of biodegradable and compostable plastics.

Under the agreement, ADM will obtain exclusive manufacturing rights and certain co-exclusive marketing rights to Metabolix proprietary PHA technology, which is protected by over 130 issued and pending US patents. The agreement provides that Metabolix will receive upfront and milestone payments for transfer and scale up of the technology. The agreement also provides for royalty payments and profit sharing by the joint venture partners.

"This agreement is a major advance toward our goal of making an array of renewable, eco-friendly alternatives to traditional petrochemical plastics widely available to the global marketplace," said Jim Barber, Metabolix's President and CEO. "ADM is a world leader in industrial fermentation, and we are delighted to combine Metabolix's groundbreaking technology with ADM's global strengths in agricultural products processing, fermentation, and logistical networking."

"As part of our continued expansion into the production of environmentally friendly biobased products, we are delighted to partner with Metabolix and enter into the next generation of polymer technology," stated G. Allen Andreas, Chairman and Chief Executive of ADM. "We believe that ADM's large scale fermentation capabilities are a perfect fit for Metabolix's patented technology. Together, we will move forward to produce renewable, biodegradable polymers at a cost which will allow their widespread incorporation into consumer products and meet the growing demands of the global market."

PHAs are a broad and versatile family of natural plastics that range in properties from rigid to highly elastic, making them suitable for films, fibers, adhesives, coatings, molded goods, and a variety of other applications. While stable to even hot water, they will biodegrade in aquatic, soil and composting environments, and even under anaerobic conditions, once their use is over. They are made using a proprietary process developed by Metabolix that converts renewable and sustainable agricultural raw materials through a fully biological fermentation process.

About Metabolix Founded in 1992, Metabolix, Inc. uses sophisticated biotechnology to produce environmentally friendly performance plastics from renewable resources. Metabolix is the world leader in applying the advanced tools of metabolic engineering and molecular biology to efficiently produce PHA biobased plastics in microbial systems and directly in non-food plant crops. For more information, please visit www.metabolix.com.

About ADM Archer Daniels Midland Company (ADM) is a world leader in agricultural processing. ADM is one of the world's largest processors of soybeans, corn, wheat and cocoa. ADM is also a leader in the production of soy meal and oil, ethanol, corn sweeteners and flour. In addition, ADM produces value-added food and feed ingredients. Headquartered in Decatur, Illinois, ADM has over 26,000 employees, more than 250 processing plants and net sales for the fiscal year ended June 30, 2004 of $36.2 billion. Additional information can be found on ADM's Web site at www.admworld.com.