BAD HOMBURG, Germany--(BUSINESS WIRE)--ALTANA AG announced today that it has sold its approx. 7.1% stake (2,360,000 shares) in GPC Biotech AG. Based on yesterday’s closing price of GPC Biotech shares on the Frankfurt Stock Exchange, the stake is valued at approximately EUR 36.3 million. The transaction represents ALTANA’s entire stake. This press release is also available on the Internet at www.altana.com.