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NOTICE OF GUARANTEED DELIVERY
FOR
TENDER OF SHARES OF COMMON STOCK
(INCLUDING THE ASSOCIATED RIGHTS TO PURCHASE
SERIES A JUNIOR PREFERRED STOCK)
OF
PATHOGENESIS CORPORATION
TO
PICARD ACQUISITION CORP.
A WHOLLY OWNED SUBSIDIARY OF
CHIRON CORPORATION
(NOT TO BE USED FOR SIGNATURE GUARANTEES)
THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK
CITY TIME, ON MONDAY, SEPTEMBER 18, 2000, UNLESS THE OFFER IS EXTENDED.
This Notice of Guaranteed Delivery, or a form substantially equivalent
hereto, must be used to accept the Offer (as defined below) (i) if certificates
for Shares (as defined below) are not immediately available, (ii) if the
procedure for book-entry transfer, as set forth in the Offer to Purchase, cannot
be completed on a timely basis or (iii) if time will not permit all required
documents to reach the Depositary on or prior to the Expiration Date. Such form
may be delivered by hand, transmitted by facsimile transmission, telegram,
telex, mail or nationally recognized overnight courier to the Depositary. See
Section 3 of the Offer to Purchase.
THE DEPOSITARY FOR THE OFFER IS:
HARRIS TRUST COMPANY OF NEW YORK
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BY MAIL: BY HAND/OVERNIGHT DELIVERY:
Wall Street Station Receive Window
P.O. Box 1023 Wall Street Plaza
New York, NY 10268-1023 88 Pine Street, 19th Floor
New York, NY 10005
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BY FACSIMILE TRANSMISSION:
(FOR ELIGIBLE INSTITUTIONS ONLY)
(212) 701-7636
FOR INFORMATION (CALL COLLECT):
(212) 701-7624
DELIVERY OF THIS NOTICE OF GUARANTEED DELIVERY TO AN ADDRESS OR TRANSMISSION
VIA FACSIMILE TO A NUMBER OTHER THAN AS SET FORTH ABOVE DOES NOT CONSTITUTE A
VALID DELIVERY TO THE DEPOSITARY.
THIS FORM IS NOT TO BE USED TO GUARANTEE SIGNATURES. IF A SIGNATURE ON A
LETTER OF TRANSMITTAL IS REQUIRED TO BE GUARANTEED BY AN "ELIGIBLE INSTITUTION"
UNDER THE INSTRUCTIONS THERETO, SUCH SIGNATURE GUARANTEE MUST APPEAR IN THE
APPLICABLE SPACE PROVIDED IN THE SIGNATURE BOX ON THE LETTER OF TRANSMITTAL.
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<PAGE>
Ladies and Gentlemen:
The undersigned hereby tenders to Picard Acquisition Corp., a Delaware
corporation ("Merger Sub") and a wholly owned subsidiary of Chiron Corporation,
a Delaware corporation ("Parent"), upon the terms and subject to the conditions
set forth in Merger Sub's Offer to Purchase dated August 21, 2000 (the "Offer to
Purchase") and the related Letter of Transmittal (which, together with any
amendments or supplements thereto, constitute the "Offer"), receipt of which is
hereby acknowledged, the number of shares set forth below of common stock, par
value $0.001 per share (the "Common Stock"), of PathoGenesis Corporation, a
Delaware corporation (the "Company"), together with the associated rights to
purchase Series A Junior Preferred Stock (the "Rights") issued pursuant to the
Rights Agreement, dated as of June 26, 1997, as amended (the "Rights
Agreement"), between the Company and Harris Trust and Savings Bank (the Common
Stock and the Rights together being referred to herein as the "Shares"),
pursuant to the guaranteed delivery procedures set forth in Section 3 of the
Offer to Purchase.
Signature(s) ___________________________________________________________________
________________________________________________________________________________
Name(s) of Record Holder(s) ____________________________________________________
PLEASE PRINT OR TYPE
Number of Shares _______________________________________________________________
Certificate No.(s) (If Available) ______________________________________________
Dated _________________________________, 2000
Address(es) ____________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
ZIP CODE
Area Code and Tel. No.(s) ______________________________________________________
Taxpayer Identification or Social Security Number ______________________________
Check box if Shares will be tendered by book-entry transfer: / /
Account Number _________________________________________________________________
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<PAGE>
THE GUARANTEE SET FORTH BELOW MUST BE COMPLETED
GUARANTEE
(NOT TO BE USED FOR SIGNATURE GUARANTEE)
The undersigned, a participant in the Security Transfer Agents Medallion
Program, the New York Stock Exchange Medallion Signature Guarantee Program, the
Stock Exchange Medallion Program or an "eligible guarantor institution" as such
term is defined in Rule 17Ad-15 under the Securities Exchange Act of 1934, as
amended, hereby (a) represents that the above named person(s) "own(s)" the
Shares tendered hereby within the meaning of Rule 14e-4 under the Securities
Exchange Act of 1934, as amended ("Rule 14e-4"), (b) represents that such tender
of Shares complies with Rule 14e-4 and (c) guarantees to deliver to the
Depositary either certificates representing the Share tendered hereby, in proper
form for transfer, or confirmation of book-entry transfer of such Shares into
the Depositary's account at The Depository Trust Company, in each case with
delivery of a properly completed and duly executed Letter of Transmittal (or a
manually signed facsimile thereof), with any required signature guarantees, or
an Agent's Message (as defined in the Offer to Purchase), and any other required
documents, within three trading days (as defined in the Offer to Purchase) after
the date hereof.
________________________________________________________________________________
NAME OF FIRM
________________________________________________________________________________
ADDRESS
________________________________________________________________________________
ZIP CODE
Area Code and Tel. No. _________________________________________________________
________________________________________________________________________________
AUTHORIZED SIGNATURE
Name ___________________________________________________________________________
PLEASE PRINT OR TYPE
Title __________________________________________________________________________
Date _________________________________, 2000
NOTE: DO NOT SEND CERTIFICATES FOR THE SHARES WITH THIS NOTICE. CERTIFICATES
SHOULD BE SENT ONLY WITH YOUR LETTER OF TRANSMITTAL.
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