Novartis has made a proposal to the independent directors of Chiron Corporation to acquire all of the remaining outstanding shares that it does not already own and has filed an amended Form 13-D as required by the US Securities and Exchange Commission. Novartis currently holds a 42.2% stake in the US biopharmaceutical company and has submitted a proposal to acquire the approximately 112 million fully diluted shares (treasury method) of Chiron for USD 40.00 per share in cash, or a total of USD 4.5 billion. This offer was made after Novartis recently conducted due diligence on Chiron with the agreement of the company's independent directors.

Novartis will seek to negotiate a customary merger agreement with the independent directors of Chiron's Board of Directors that would be subject to approval by a majority of the Chiron shares not owned by Novartis. This transaction could be completed promptly, but there can be no assurance that an agreement will be reached on a transaction.

Chiron Corporation, which had 2004 sales of USD 1.7 billion, operates in three business segments: Vaccines, which offers more than 30 products including influenza, meningococcal, travel and paediatric vaccines; Blood Testing; and BioPharmaceuticals. Founded in 1981, Chiron has more than 5,300 employees worldwide.

Meanwhile, Chiron Corporation has confirmed that it had received an offer from Novartis AG to acquire the approximately 58% of Chiron shares that Novartis does not already own for $40 per Chiron share in cash.

The Chiron Board of Directors, excluding the three Novartis directors, will thoroughly evaluate the offer in due course with the assistance of Chiron's financial advisors, Morgan Stanley and Credit Suisse First Boston, said a release.