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OFFER TO PURCHASE FOR CASH
ALL OUTSTANDING SHARES OF COMMON STOCK
(INCLUDING THE ASSOCIATED RIGHTS TO PURCHASE SERIES A JUNIOR PREFERRED STOCK)
OF
PATHOGENESIS CORPORATION
AT
$38.50 NET PER SHARE
BY
PICARD ACQUISITION CORP.
A WHOLLY OWNED SUBSIDIARY OF
CHIRON CORPORATION
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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.
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August 21, 2000
To Our Clients:
Enclosed for your consideration are the 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, collectively constitute the
"Offer") in connection with the offer by Picard Acquisition Corp., a Delaware
corporation ("Merger Sub") and a wholly owned subsidiary of Chiron Corporation,
a Delaware corporation ("Parent"), to purchase all outstanding shares 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 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"),
at a purchase price of $38.50 per Share, net to the seller in cash, without
interest (the "Offer Price"), upon the terms and subject to the conditions set
forth in the Offer to Purchase. The Offer is being made pursuant to an Agreement
and Plan of Merger dated as of August 13, 2000 among Parent, Merger Sub and the
Company (the "Merger Agreement").
WE ARE THE HOLDER OF RECORD OF THE SHARES HELD FOR YOUR ACCOUNT. A TENDER OF
SUCH SHARES CAN BE MADE ONLY BY US AS THE HOLDER OF RECORD AND PURSUANT TO YOUR
INSTRUCTIONS. THE ENCLOSED LETTER OF TRANSMITTAL IS FURNISHED TO YOU FOR YOUR
INFORMATION ONLY AND CANNOT BE USED BY YOU TO TENDER SHARES HELD BY US FOR YOUR
ACCOUNT.
We request instructions as to whether you wish us to tender any or all of
the Shares held by us for your account, upon the terms and subject to the
conditions set forth in the Offer to Purchase. Your attention is invited to the
following:
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1. The tender price is $38.50 per Share, net to you in cash without
interest.
2. The Offer is being made for all outstanding Shares.
3. THE BOARD OF DIRECTORS OF THE COMPANY HAS DETERMINED THAT THE OFFER AND
THE MERGER ARE ADVISABLE AND IN THE BEST INTERESTS OF THE COMPANY'S
STOCKHOLDERS, AND UNANIMOUSLY RECOMMENDS THAT THE COMPANY'S STOCKHOLDERS
ACCEPT THE OFFER AND TENDER THEIR SHARES PURSUANT TO THE OFFER.
4. THE OFFER AND WITHDRAWAL RIGHTS EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY
TIME, ON MONDAY, SEPTEMBER 18, 2000, UNLESS THE OFFER IS EXTENDED.
5. The Offer is conditioned upon, among other things, (i) there being
validly tendered and not withdrawn prior to the expiration of the Offer
that number of Shares which, when added together with all other Shares
owned by Parent and its subsidiaries, would represent at least a majority
of the outstanding Shares (determined on a fully diluted basis for all
outstanding stock options and other rights (other than the rights, if
such rights are not at the time exercisable) to acquire Shares
outstanding on the date of purchase), (ii) any requisite waiting period
under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as
amended, applicable to the purchase of Shares pursuant to the Offer or
the Merger described herein having been terminated or having expired, and
(iii) the applicable waiting periods under certain foreign antitrust and
competition laws having been terminated or having expired, except for
such waiting periods the failure of which to terminate or expire is not
reasonably likely to have a Parent Material Adverse Effect or a Company
Material Adverse Effect (as such terms are defined in the Offer to
Purchase) or to provide a reasonable basis to conclude that Parent,
Merger Sub or the Company or any of their respective directors, officers,
agents, advisors or other representatives would be subject to the risk of
criminal liability.
6. Any stock transfer taxes applicable to the sale of the Shares to Merger
Sub pursuant to the Offer will be paid by Purchaser, except as otherwise
provided in Instruction 6 of the Letter of Transmittal.
The Offer is not being made to (nor will tenders be accepted from or on
behalf of) holders of the Shares in any jurisdiction in which the making of the
Offer or the acceptance thereof would not be in compliance with the laws of such
jurisdiction. However, Merger Sub may, in its sole discretion, take such action
as it may deem necessary to make the Offer in any such jurisdiction and extend
the Offer to holders of the Shares in such jurisdiction.
Neither Parent nor Merger Sub is aware of any jurisdiction in which the
making of the Offer or the acceptance of the Shares in connection therewith
would not be in compliance with the laws of such jurisdiction.
If you wish to have us tender any or all of your Shares, please so instruct
us by completing, executing and returning to us the instruction form set forth
on the reverse side of this letter. An envelope to return your instructions to
us is enclosed. If you authorize the tender of your Shares, all such Shares will
be tendered unless otherwise specified on the reverse side of this letter. YOUR
INSTRUCTIONS SHOULD BE FORWARDED TO US IN AMPLE TIME TO PERMIT US TO SUBMIT A
TENDER ON YOUR BEHALF PRIOR TO THE EXPIRATION OF THE OFFER.
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INSTRUCTIONS WITH RESPECT TO THE
OFFER TO PURCHASE FOR CASH
ALL OUTSTANDING SHARES OF COMMON STOCK
OF
PATHOGENESIS CORPORATION
(INCLUDING THE ASSOCIATED RIGHTS TO PURCHASE SERIES A
JUNIOR PREFERRED STOCK)
BY
PICARD ACQUISITION CORP.
A WHOLLY OWNED SUBSIDIARY OF
CHIRON CORPORATION
The undersigned acknowledge(s) receipt of your letter and the enclosed Offer
to Purchase dated August 21, 2000 and the related Letter of Transmittal in
connection with the Offer (as defined below) by Picard Acquisition Corp., a
Delaware corporation and a wholly owned subsidiary of Chiron Corporation, a
Delaware corporation, to purchase all outstanding shares 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, between the Company and
Harris Trust and Savings Bank (the Common Stock and the Rights together being
referred to herein as the "Shares"), at a purchase price of $38.50 per Share,
net to the seller in cash, without interest, on the terms and subject to the
conditions set forth in the Offer to Purchase and in the related Letter of
Transmittal (which, together with any amendments or supplements hereto or
thereto, collectively constitute the "Offer").
This will instruct you to tender the number of Shares indicated below (or if
no number is indicated below, all Shares) held by you for the account of the
undersigned, upon the terms and subject to the conditions set forth in the
Offer.
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Number of Shares tendered:*_____________________________________________________
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Certificate Nos. (if available): _______________________________________________
Check the box if Shares will be tendered by book-entry transfer: / /
Account No: ____________________________________________________________________
Dated: __________________________________________________________________ , 2000
SIGN HERE
Signature(s): __________________________________________________________________
Please type or print address(es): ______________________________________________
Area Code and Telephone Number: ________________________________________________
Taxpayer Identification or Social Security Number(s): __________________________
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* Unless otherwise indicated, it will be assumed that all Shares held by us
for your account are to be tendered.
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