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<P ALIGN="CENTER"><FONT SIZE=2><B>As filed with the Securities and Exchange Commission on January&nbsp;31, 2002  </B></FONT></P>

<P ALIGN="RIGHT"><FONT SIZE=2><B> Registration No.&nbsp;333-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </B></FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=5><B>SECURITIES AND EXCHANGE COMMISSION<BR>  </B></FONT><FONT SIZE=2><B>Washington, D.C. 20549  </B></FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=5><B>FORM S-8<BR>  </B></FONT><FONT SIZE=2><B>REGISTRATION STATEMENT<BR>
UNDER<BR>
THE SECURITIES ACT OF 1933  </B></FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=5><B>CHIRON CORPORATION<BR>  </B></FONT><FONT SIZE=2>(Exact Name Of Registrant As Specified In Its Charter) </FONT></P>

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<TD WIDTH="50%" ALIGN="CENTER"><FONT SIZE=2><B>Delaware</B></FONT><FONT SIZE=2><BR>
(State or other jurisdiction of<BR>
incorporation or organization)</FONT></TD>
<TD WIDTH="50%" ALIGN="CENTER"><FONT SIZE=2><B>94-2754621</B></FONT><FONT SIZE=2><BR>
(I.R.S. Employer<BR>
Identification No.)<BR></FONT>
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<P ALIGN="CENTER"><FONT SIZE=2><B>4560 Horton St., Emeryville, California 94608<BR>
(510)&nbsp;655-8730<BR>  </B></FONT><FONT SIZE=2>(Address of Principal Executive Offices, including<BR>
area code and telephone number) (Zip Code) </FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=2><B>CHIRON 1991 STOCK OPTION PLAN<BR>  </B></FONT><FONT SIZE=2>(Full title of the plan) </FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=2><B>WILLIAM G. GREEN, ESQ.<BR>
SENIOR VICE PRESIDENT AND GENERAL COUNSEL<BR>
CHIRON CORPORATION<BR>
4560 Horton Street, Emeryville, California 94608<BR>  </B></FONT><FONT SIZE=2>(Name and address, including zip code, of agent for service) </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B>(510)&nbsp;655-8730<BR>  </B></FONT><FONT SIZE=2>(Telephone number, including area code, of agent for service) </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B>CALCULATION OF REGISTRATION FEE  </B></FONT></P>

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<TD WIDTH="34%" ALIGN="CENTER" VALIGN="BOTTOM"><FONT SIZE=1><B>Title of securities to be registered</B></FONT></TD>
<TD WIDTH="1%" VALIGN="BOTTOM"><FONT SIZE=1>&nbsp;</FONT></TD>
<TD WIDTH="16%" ALIGN="CENTER" VALIGN="BOTTOM"><FONT SIZE=1><B>Amount to be registered</B></FONT></TD>
<TD WIDTH="1%" VALIGN="BOTTOM"><FONT SIZE=1>&nbsp;</FONT></TD>
<TD WIDTH="14%" ALIGN="CENTER" VALIGN="BOTTOM"><FONT SIZE=1><B>Proposed maximum offering price per share</B></FONT></TD>
<TD WIDTH="1%" VALIGN="BOTTOM"><FONT SIZE=1>&nbsp;</FONT></TD>
<TD WIDTH="19%" ALIGN="CENTER" VALIGN="BOTTOM"><FONT SIZE=1><B>Proposed maximum aggregate offering price</B></FONT></TD>
<TD WIDTH="1%" VALIGN="BOTTOM"><FONT SIZE=1>&nbsp;</FONT></TD>
<TD WIDTH="14%" ALIGN="CENTER" VALIGN="BOTTOM"><FONT SIZE=1><B>Amount of registration fee</B></FONT></TD>
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<TD COLSPAN=9 VALIGN="BOTTOM"><HR NOSHADE></TD>
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<TD WIDTH="34%"><FONT SIZE=2>Common Stock, $0.01<BR>
par value (1991 Stock<BR>
Option Plan)</FONT></TD>
<TD WIDTH="1%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="16%" ALIGN="CENTER"><FONT SIZE=2>13,000,000(1)</FONT></TD>
<TD WIDTH="1%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="14%" ALIGN="CENTER"><FONT SIZE=2>$41.8650(2)</FONT></TD>
<TD WIDTH="1%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="19%" ALIGN="CENTER"><FONT SIZE=2>$544,245,000(2)</FONT></TD>
<TD WIDTH="1%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="14%" ALIGN="CENTER"><FONT SIZE=2>$50,070.54</FONT></TD>
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<DT style='margin-bottom:-11pt;'><FONT SIZE=2>(1)</FONT></DT><DD><FONT SIZE=2>This
registration statement shall also cover any additional shares of Common Stock which become issuable under the Chiron 1991 Stock Option Plan, by reason of any stock dividend,
stock split, recapitalization or other similar transaction effected without the receipt of consideration which results in an increase in the number of the registrant's outstanding shares of Common
Stock. </FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2>(2)</FONT></DT><DD><FONT SIZE=2>Calculated
solely for the purposes of this offering under Rule&nbsp;457(h) of the Securities Act of 1933 on the basis of the average of the high and low selling prices per share of
Common Stock of Chiron Corporation on January&nbsp;30, 2002, as reported by the NASDAQ National Market System. </FONT></DD></DL>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><B>This registration statement shall become effective immediately upon filing with the Securities and Exchange Commission, and sales of the
registered securities will begin as soon as reasonably practicable after such effective date.  </B></FONT></P>

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<P><FONT SIZE=2>Also relates to Registration File Nos. 33-35182, 33-20181, 2-90595, 33-44477, 33-65024, 33-65177,
333-10419, 333-28257 and 333-43424 pursuant to Rule&nbsp;429 under the Securities Act of 1933. </FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=2><A
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<BR></FONT><FONT SIZE=2><B>PART II    <BR>  </B></FONT></P>

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<A NAME="toc_be1059_2"> </A>
<BR></FONT><FONT SIZE=2><B>INFORMATION REQUIRED IN THE REGISTRATION STATEMENT    <BR>  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The contents of the registration statement on Form&nbsp;S-8 (File No.&nbsp;33-44477), filed by Chiron Corporation (the "registrant")
with the Securities and Exchange Commission on December&nbsp;12, 1991, are hereby incorporated by reference herein. </FONT></P>

<P><FONT SIZE=2><B>ITEM 5.&nbsp;&nbsp;&nbsp;&nbsp;INTERESTS OF NAMED EXPERTS AND COUNSEL.  </B></FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;William G. Green, who has provided an opinion to the registrant on the validity of the securities being registered which is Exhibit&nbsp;5 to this registration
statement, is Senior Vice President, General Counsel and Secretary of the registrant. </FONT></P>

<P><FONT SIZE=2><B>ITEM 8.&nbsp;&nbsp;&nbsp;&nbsp;EXHIBITS.  </B></FONT></P>

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<TH WIDTH="10%" ALIGN="CENTER"><FONT SIZE=1><B>Exhibit<BR>
Number</B></FONT><HR NOSHADE></TH>
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<TH WIDTH="88%" ALIGN="LEFT"><FONT SIZE=1><B>Exhibit<BR> </B></FONT><HR NOSHADE></TH>
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&nbsp;&nbsp;5</FONT></TD>
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Opinion of William G. Green.</FONT></TD>
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23.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
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Consent of KPMG LLP, Independent Auditors.</FONT></TD>
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23.2</FONT></TD>
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Consent of William G. Green is contained in Exhibit 5.</FONT></TD>
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24</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="88%"><FONT SIZE=2><BR>
Power of Attorney. Reference is made to pages II-2 through II-3 of this registration statement.</FONT></TD>
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<TD WIDTH="10%"><FONT SIZE=2><BR>
99.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="88%"><FONT SIZE=2><BR>
Chiron 1991 Stock Option Plan, as amended and restated.</FONT></TD>
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<P ALIGN="CENTER"><FONT SIZE=2>II-1</FONT></P>

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<BR></FONT><FONT SIZE=2><B>SIGNATURES    <BR>  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form&nbsp;S-8 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of
Emeryville, State of California, on the 31<SUP>st</SUP> day of January, 2002. </FONT></P>

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<TD WIDTH="42%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD COLSPAN=2><FONT SIZE=2>CHIRON CORPORATION</FONT></TD>
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<TD WIDTH="42%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="6%"><BR><FONT SIZE=2>By:</FONT></TD>
<TD WIDTH="49%"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>SE&Aacute;N P. LANCE</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Name: Se&aacute;n P. Lance<BR>
Title: </FONT><FONT SIZE=2><I>President; Chief Executive Officer and<BR>
Chairman of the Board</I></FONT></TD>
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<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="jc1059_power_of_attorney"> </A>
<A NAME="toc_jc1059_2"> </A>
<BR></FONT><FONT SIZE=2><B>POWER OF ATTORNEY    <BR>  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;KNOW ALL PERSONS BY THESE PRESENTS, that the undersigned officers and directors of Chiron Corporation, a Delaware corporation, do hereby constitute and appoint
Se&aacute;n P. Lance and James R. Sulat, and each of them, the lawful attorneys and agents or attorney and agent with full power and authority to do any and all acts and things and to execute
any and all instruments which said attorneys and agents, and any one of them, determine may be necessary or advisable or required to enable said corporation to comply with the Securities Act of 1933,
as amended, and any rules or regulations or requirements of the Securities and Exchange Commission in connection with this registration statement. Without limiting the generality of the foregoing
power and authority, the powers granted include the power and authority to sign the names of the undersigned officers and directors in the capacities indicated below this registration statement, to
any and all amendments, both pre-effective and post-effective, and supplements to this registration statement, and to any and all instruments or
documents filed as part of or in conjunction with this registration statement or amendments or supplements thereof, and each of the undersigned hereby ratifies and confirms all that said attorneys and
agents, or any one of them shall do or cause to be done by virtue hereof. This power of attorney may be signed in several counterparts. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;IN
WITNESS WHEREOF, each of the undersigned has executed this power of attorney as of the date indicated. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Pursuant
to the requirements of the Securities Act of 1933, this registration statement has been signed below by the following persons in the capacities and on the date indicated. </FONT></P>

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<TH WIDTH="34%" ALIGN="LEFT"><FONT SIZE=1><B>Signature<BR> </B></FONT><HR NOSHADE></TH>
<TH WIDTH="3%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="40%" ALIGN="CENTER"><FONT SIZE=1><B>Title</B></FONT><HR NOSHADE></TH>
<TH WIDTH="3%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="21%" ALIGN="CENTER"><FONT SIZE=1><B>Date</B></FONT><HR NOSHADE></TH>
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<TD WIDTH="34%" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>SE&Aacute;N P. LANCE</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Se&aacute;n P. Lance</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
President, Chief Executive Officer and<BR>
Chairman of the Board of Directors<BR>
(Principal Executive Officer)</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="21%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
January 31, 2002</FONT></TD>
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<TD WIDTH="34%" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>JAMES R. SULAT</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> James R. Sulat</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Vice President, Chief Financial Officer<BR>
(Principal Financial Officer)</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="21%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
January 31, 2002</FONT></TD>
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<TD WIDTH="34%" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>DAVID V. SMITH</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> David V. Smith</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Vice President<BR>
(Principal Accounting Officer)</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="21%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
January 31, 2002</FONT></TD>
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/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>RAYMUND BREU</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Raymund Breu</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="21%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
January 31, 2002  </FONT></TD>
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<P ALIGN="CENTER"><FONT SIZE=2>II-2</FONT></P>

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/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>VAUGHN D. BRYSON</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Vaughn D. Bryson</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="21%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
January 31, 2002</FONT></TD>
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/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>LEWIS W. COLEMAN</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Lewis W. Coleman</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="21%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
January 31, 2002</FONT></TD>
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<TD WIDTH="34%" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>PIERRE E. DOUAZE</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Pierre E. Douaze</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="21%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
January 31, 2002</FONT></TD>
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<TD WIDTH="34%" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>PAUL L. HERRLING</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Paul L. Herrling</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="21%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
January 31, 2002</FONT></TD>
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<TD WIDTH="34%" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>EDWARD E. PENHOET</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Edward E. Penhoet</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="21%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
January 31, 2002</FONT></TD>
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<TD WIDTH="34%" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>WILLIAM J. RUTTER</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> William J. Rutter</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="21%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
January 31, 2002</FONT></TD>
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<TD WIDTH="34%" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>JACK W. SCHULER</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Jack W. Schuler</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="21%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
January 31, 2002</FONT></TD>
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<TD WIDTH="34%" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>PIETER J. STRIJKERT</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Pieter J. Strijkert</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="40%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="21%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
January 31, 2002</FONT></TD>
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<P ALIGN="CENTER"><FONT SIZE=2>II-3</FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=5><B>SECURITIES AND EXCHANGE COMMISSION<BR>  </B></FONT><FONT SIZE=2><B>Washington, D.C. 20549  </B></FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=5><B>EXHIBITS<BR>
TO<BR>
FORM S-8  </B></FONT></P>

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SECURITIES ACT OF 1933  </B></FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=5><B>CHIRON CORPORATION  </B></FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=5><B> <A NAME="ka1059_exhibit_index"> </A>
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<BR>    </B></FONT><FONT SIZE=2><B>EXHIBIT INDEX    <BR>  </B></FONT></P>

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&nbsp;&nbsp;5</FONT></TD>
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Opinion of William G. Green.</FONT></TD>
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23.1</FONT></TD>
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Consent of KPMG LLP, Independent Auditors.</FONT></TD>
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23.2</FONT></TD>
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Consent of William G. Green is contained in Exhibit 5.</FONT></TD>
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24</FONT></TD>
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Power of Attorney. Reference is made to pages&nbsp;II-2 through II-3 of this registration statement.</FONT></TD>
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99.1</FONT></TD>
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Chiron 1991 Stock Option Plan, as amended and restated.</FONT></TD>
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<P><br><A NAME="02SFO1059_1">QuickLinks</A><br></P><!-- TOC_BEGIN -->
<FONT SIZE=2><A HREF="#toc_be1059_1">PART II</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_be1059_2">INFORMATION REQUIRED IN THE REGISTRATION STATEMENT</A></FONT><BR>

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<FONT SIZE=2><A HREF="#toc_jc1059_1">SIGNATURES</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_jc1059_2">POWER OF ATTORNEY</A></FONT><BR>
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<FONT SIZE=2><A HREF="#toc_ka1059_1">EXHIBIT INDEX</A></FONT><BR>
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{"company-data": {"conformed-name": "CHIRON CORP", "cik": "0000706539", "assigned-sic": "2834", "irs-number": "942754624", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-81794", "film-number": "02523345"}, "business-address": {"street1": "4560 HORTON ST", "city": "EMERYVILLE", "state": "CA", "zip": "94608", "phone": "5106558730"}}
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As filed with the Securities and Exchange Commission on January 31, 2002
Registration No. 333-
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM S-8
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933
CHIRON CORPORATION
(Exact Name Of Registrant As Specified In Its Charter)
Delaware
(State or other jurisdiction of
incorporation or organization)
94-2754621
(I.R.S. Employer
Identification No.)
4560 Horton St., Emeryville, California 94608
(510) 655-8730
(Address of Principal Executive Offices, including
area code and telephone number) (Zip Code)
CHIRON 1991 STOCK OPTION PLAN
(Full title of the plan)
WILLIAM G. GREEN, ESQ.
SENIOR VICE PRESIDENT AND GENERAL COUNSEL
CHIRON CORPORATION
4560 Horton Street, Emeryville, California 94608
(Name and address, including zip code, of agent for service)
(510) 655-8730
(Telephone number, including area code, of agent for service)
CALCULATION OF REGISTRATION FEE
Title of securities to be registered
Amount to be registered
Proposed maximum offering price per share
Proposed maximum aggregate offering price
Amount of registration fee
Common Stock, $0.01
par value (1991 Stock
Option Plan)
13,000,000(1)
$41.8650(2)
$544,245,000(2)
$50,070.54
(1)
This
registration statement shall also cover any additional shares of Common Stock which become issuable under the Chiron 1991 Stock Option Plan, by reason of any stock dividend,
stock split, recapitalization or other similar transaction effected without the receipt of consideration which results in an increase in the number of the registrant's outstanding shares of Common
Stock.
(2)
Calculated
solely for the purposes of this offering under Rule 457(h) of the Securities Act of 1933 on the basis of the average of the high and low selling prices per share of
Common Stock of Chiron Corporation on January 30, 2002, as reported by the NASDAQ National Market System.
This registration statement shall become effective immediately upon filing with the Securities and Exchange Commission, and sales of the
registered securities will begin as soon as reasonably practicable after such effective date.
Also relates to Registration File Nos. 33-35182, 33-20181, 2-90595, 33-44477, 33-65024, 33-65177,
333-10419, 333-28257 and 333-43424 pursuant to Rule 429 under the Securities Act of 1933.
PART II
INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
The contents of the registration statement on Form S-8 (File No. 33-44477), filed by Chiron Corporation (the "registrant")
with the Securities and Exchange Commission on December 12, 1991, are hereby incorporated by reference herein.
ITEM 5.    INTERESTS OF NAMED EXPERTS AND COUNSEL.
William G. Green, who has provided an opinion to the registrant on the validity of the securities being registered which is Exhibit 5 to this registration
statement, is Senior Vice President, General Counsel and Secretary of the registrant.
ITEM 8.    EXHIBITS.
Exhibit
Number
Exhibit
5
Opinion of William G. Green.
23.1
Consent of KPMG LLP, Independent Auditors.
23.2
Consent of William G. Green is contained in Exhibit 5.
24
Power of Attorney. Reference is made to pages II-2 through II-3 of this registration statement.
99.1
Chiron 1991 Stock Option Plan, as amended and restated.
II-1
SIGNATURES
Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of
Emeryville, State of California, on the 31
st
day of January, 2002.
CHIRON CORPORATION
By:
/s/
SEÁN P. LANCE
Name: Seán P. Lance
Title:
President; Chief Executive Officer and
Chairman of the Board
POWER OF ATTORNEY
KNOW ALL PERSONS BY THESE PRESENTS, that the undersigned officers and directors of Chiron Corporation, a Delaware corporation, do hereby constitute and appoint
Seán P. Lance and James R. Sulat, and each of them, the lawful attorneys and agents or attorney and agent with full power and authority to do any and all acts and things and to execute
any and all instruments which said attorneys and agents, and any one of them, determine may be necessary or advisable or required to enable said corporation to comply with the Securities Act of 1933,
as amended, and any rules or regulations or requirements of the Securities and Exchange Commission in connection with this registration statement. Without limiting the generality of the foregoing
power and authority, the powers granted include the power and authority to sign the names of the undersigned officers and directors in the capacities indicated below this registration statement, to
any and all amendments, both pre-effective and post-effective, and supplements to this registration statement, and to any and all instruments or
documents filed as part of or in conjunction with this registration statement or amendments or supplements thereof, and each of the undersigned hereby ratifies and confirms all that said attorneys and
agents, or any one of them shall do or cause to be done by virtue hereof. This power of attorney may be signed in several counterparts.
IN
WITNESS WHEREOF, each of the undersigned has executed this power of attorney as of the date indicated.
Pursuant
to the requirements of the Securities Act of 1933, this registration statement has been signed below by the following persons in the capacities and on the date indicated.
Signature
Title
Date
/s/
SEÁN P. LANCE
Seán P. Lance
President, Chief Executive Officer and
Chairman of the Board of Directors
(Principal Executive Officer)
January 31, 2002
/s/
JAMES R. SULAT
James R. Sulat
Vice President, Chief Financial Officer
(Principal Financial Officer)
January 31, 2002
/s/
DAVID V. SMITH
David V. Smith
Vice President
(Principal Accounting Officer)
January 31, 2002
/s/
RAYMUND BREU
Raymund Breu
Director
January 31, 2002
II-2
/s/
VAUGHN D. BRYSON
Vaughn D. Bryson
Director
January 31, 2002
/s/
LEWIS W. COLEMAN
Lewis W. Coleman
Director
January 31, 2002
/s/
PIERRE E. DOUAZE
Pierre E. Douaze
Director
January 31, 2002
/s/
PAUL L. HERRLING
Paul L. Herrling
Director
January 31, 2002
/s/
EDWARD E. PENHOET
Edward E. Penhoet
Director
January 31, 2002
/s/
WILLIAM J. RUTTER
William J. Rutter
Director
January 31, 2002
/s/
JACK W. SCHULER
Jack W. Schuler
Director
January 31, 2002
/s/
PIETER J. STRIJKERT
Pieter J. Strijkert
Director
January 31, 2002
II-3
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
EXHIBITS
TO
FORM S-8
UNDER THE
SECURITIES ACT OF 1933
CHIRON CORPORATION
EXHIBIT INDEX
Exhibit
Number
Exhibits
5
Opinion of William G. Green.
23.1
Consent of KPMG LLP, Independent Auditors.
23.2
Consent of William G. Green is contained in Exhibit 5.
24
Power of Attorney. Reference is made to pages II-2 through II-3 of this registration statement.
99.1
Chiron 1991 Stock Option Plan, as amended and restated.
QuickLinks
PART II
INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
SIGNATURES
POWER OF ATTORNEY
EXHIBIT INDEX