News Release Details

BOSTON, Sept. 21 /PRNewswire-FirstCall/ -- Cabot Corporation (NYSE: CBT) today announced that it priced a public offering of $300 million of 5% senior unsecured notes due 2016. The notes are being sold to the public at 99.322%, resulting in a yield to maturity of 5.1%. Cabot will pay interest on the notes semi-annually on October 1 and April 1 of each year, beginning on April 1, 2010. The sale of the notes is expected to close on September 24, 2009, subject to customary closing conditions. Cabot intends to use the net proceeds of the offering to repay borrowings under its revolving credit facility and for general corporate purposes.

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J.P.Morgan and BofA Merrill Lynch are the joint book-running managers for the offering. The offering of these securities is being made only by means of a prospectus and related prospectus supplement. Electronic copies of the prospectus and related prospectus supplement may be obtained by visiting the SEC website at www.sec.gov. Alternatively, this information may be requested by mail from J.P.Morgan Securities Inc., Attention: High Grade Syndicate Desk, 270 Park Avenue, 8(th) Floor, New York, NY 10017 or Banc of America Securities LLC, Prospectus Department, 100 West 33(rd) Street, 3(rd) Floor, New York, NY 10001.

This press release shall not constitute an offer to sell or the solicitation of an offer to buy, nor shall there be any sale of these securities in any state or jurisdiction in which such an offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.

About Cabot Corporation- Cabot Corporation, headquartered in Boston, Massachusetts, is a global performance materials company. Cabot's major products are carbon black, fumed silica, inkjet colorants, aerogel, capacitor materials, and cesium formate drilling fluids. The Company's website is: http://www.cabot-corp.com.

Forward-Looking Statements- This press release contains forward-looking statements based on management's current expectations. All statements that address expectations or projections about the future (including our expectation of use of proceeds of the public offering) and long term strategy for growth are forward-looking statements. Some of the forward-looking statements may be identified by words like "expects," "anticipates," "plans," "intends," "projects," "indicates," and similar expressions. These statements are not guarantees of future performance and involve a number of risks, uncertainties and assumptions. Many factors, including those discussed more fully elsewhere in this release and in documents filed with the Securities and Exchange Commission by Cabot, particularly its latest annual report on Form 10-K, could cause results to differ materially from those stated.

SOURCE: Cabot Corporation

Susannah Robinson,
Director, Investor Relations of Cabot Corporation,
+1-617-342-6129,
susannah_robinson@cabot-corp.com