The families controlling Roche Holding AG (ROG.VX) Wednesday said they have extended their pool indefinitely, securing their grip on the Swiss pharmaceutical giant.

The extension of the contract, which was due to expire at the end of 2009, signals the families' commitment to preserve Roche's "independent and autonomous character for the long term," said Scobag Privatbank, the family bank.

Members of the Oeri and Hoffmann families, among the wealthiest individuals in Switzerland, own more than 80 million bearer shares, or just over 50% of Roche's shares issued. On top of that, individual family members own an unspecified amount of stock outside the pool.

The pact includes provisions on the exercising of the voting rights and restrictions regarding the disposal of the shares, which weren't specified.

There were some changes within the group: Beatrice Oeri has decided to leave the pool as of Apr. 1, 2009, while the first representatives of the fifth generation will join. The pool will in future comprise nine members.

Basel-based Roche plans to acquire the remainder of U.S.-based biotechnology company Genentech Inc. (DNA), in which it owns a majority.

Another large shareholder of Roche is cross-town rival Novartis AG (NOVN.VX) which owns a third of Roche's voting rights.

The Roche certificate, the more liquid of the two share categories, closed at 166.50 Swiss francs on Tuesday. It has gained 2.5% so far this year.

Company Web Site: http://www.roche.com

-By Martin Gelnar, Dow Jones Newswires, +41 43 443 8042; martin.gelnar@dowjones.com

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