[LETTERHEAD]
December 19, 1996
▇▇. ▇▇▇▇▇▇▇ ▇▇▇
Ciba-Geigy Limited
Rechtsabteilung
CH-▇▇▇▇ ▇▇▇▇▇, ▇▇▇▇▇▇▇▇▇▇▇
Dear ▇▇▇▇▇▇▇:
The purpose of this letter is to set forth our understanding of our agreement
regarding compensation paid by ▇▇▇▇▇▇ for director services performed by
employees of Ciba-Geigy Limited.
1. ▇▇. ▇▇▇▇ ▇▇▇▇▇▇, ▇▇. ▇▇▇▇▇▇▇▇ ▇'▇▇▇▇▇▇▇▇▇▇▇, and ▇▇▇▇▇▇ ▇▇▇▇▇▇, the "Ciba
directors", are employees of ▇▇▇▇ ▇▇▇▇▇ Limited, and have performed services
as directors of Chiron Corporation beginning on January 4, 1995. Chiron
Corporation has made cash payments to the Ciba directors in return for such
services. These individuals are required to pay over to Ciba-Geigy Limited
such amounts received for director services in accordance with the terms of
their employment with Ciba-Geigy Limited. All amounts paid since January 4,
1995 for board meetings and retainer fees were paid by the Ciba directors to
Ciba-Geigy Limited.
2. Ciba-Geigy Limited desires to have payment made directly to Ciba-Geigy
Limited for fees paid by Chiron for director services performed by employees
of Ciba-Geigy Limited.
3. Based on the above, all future cash payments made by Chiron in return for
directors services performed by employees of Ciba-Geigy Limited will be
remitted directly to Ciba-Geigy Limited. Payments will be made in U.S.
dollars, drawn on a U.S. bank, and forwarded directly to you or such other
party you may designate.
Please sign where indicated below to confirm your agreement with the above
arrangement.
Very truly yours,
/s/ ▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇
▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇, Esq.
Senior Vice President & General Counsel
I agree with the above arrangement.
/s/▇▇. ▇▇▇▇▇▇▇ ▇▇▇ Dec. 20, 1996
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▇▇. ▇▇▇▇▇▇▇ ▇▇▇, Senior Legal Counsel Date
Ciba Geigy Limited
/s/▇▇. ▇▇▇▇▇ ▇▇▇▇▇▇ Dec. 20, 1996
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▇▇. ▇▇▇▇▇ ▇▇▇▇▇▇, Head of Date
Corporate Legal & Tax Matters