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PROSPECTUS SUPPLEMENT FILED PURSUANT TO RULE 424(B)(3) AND (C)
(TO PROSPECTUS DATED JULY 20, 1998) FILE NUMBER 333-56765
ARBOR SOFTWARE CORPORATION
$100,000,000 PRINCIPAL AMOUNT OF 4 1/2% CONVERTIBLE
SUBORDINATED NOTES DUE 2005
(INTEREST PAYABLE MARCH 15 AND SEPTEMBER 15)
1,774,403 SHARES OF COMMON STOCK
This Prospectus Supplement supplements the Prospectus dated July 20, 1998
relating to (i) $100,000,000 aggregate principal amount of 4 1/2% Convertible
Subordinated Notes due 2005 (the "Notes") of Arbor Software Corporation, a
Delaware corporation (the "Company"), and (ii) 1,774,403 shares of common stock,
par value $.001 per share (the "Common Stock"), of the Company which are
initially issuable upon conversion of the Notes plus such additional
indeterminate number of shares of Common Stock of the Company as may become
issuable upon conversion of the Notes as a result of adjustments to the
conversion price (the "Shares"). The Notes and the Shares are being offered for
the account of the holders thereof. The Notes were initially acquired from the
Company by Morgan Stanley & Co. Incorporated and BancAmerica Robertson Stephens
in March 1998 in connection with a private offering. This Prospectus Supplement
is incorporated by reference into the Prospectus, and all terms used herein
shall have the meaning assigned to them in the Prospectus. On August 20, 1998
the closing price of the Common Stock of the Company on the Nasdaq National
Market was $31 7/16. The Common Stock of the Company is traded under the symbol
"ARSW."
The section entitled "Selling Securityholders" is hereby amended to include
the following table:
<TABLE>
<CAPTION>
PRINCIPAL AMOUNT OF NOTES PRINCIPAL AMOUNT OF
BENEFICIALLY OWNED THAT PERCENTAGE OF NOTES NOTES TO BE SOLD
NAME OF SELLING SECURITYHOLDER MAY BE SOLD(1) OUTSTANDING (2)(3)
------------------------------ ------------------------- ------------------- -------------------
<S> <C> <C> <C>
Christian Science Trustees For
Gifts and Endowments(4)........................ $ 50,000 * 887
Donaldson, Lufkin & Jenrette Sec. Corp. ......... $600,000 * 10,646
First Church of Christ,
Scientist--Endowment(4)........................ $ 55,000 * 976
General Motors Employees Domestic
Group Trust(4)................................. $795,000 * 14,106
Hull Overseas, Ltd. ............................. $350,000 * 6,210
Thermo Electron Balanced Investment Fund(4)...... $100,000 * 1,774
</TABLE>
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* Less than 1%.
(1) Unless otherwise noted, represents the aggregate principal amount of Notes
beneficially owned by the Selling Securityholder as of August 20, 1998 and
prior to giving effect to the sale of the Notes being offered hereby.
(2) Assumes conversion of the full amount of Notes held by such holder at the
initial conversion price of $56.357 per share; such conversion price is
subject to adjustment as described under "Description of the
Notes -- Conversion of Notes." Accordingly, the number of shares of Common
Stock issuable upon conversion of the Notes may increase or decrease from
time to time. Under the terms of the Indenture (as defined), fractional
shares will not be issued upon conversion of the Notes; cash will be paid in
lieu of fractional shares, if any.
(3) As of August 20, 1998, the Selling Securityholders did not beneficially own
any shares of Common Stock of the Company, other than the shares of Common
Stock into which the Notes beneficially owned by the Selling Securityholder
are convertible.
(4) Represents additional Notes and Shares being registered by the Selling
Securityholder.
The preceding table has been prepared based upon the information furnished
to the Company by the Selling Securityholders named therein.
SEE "RISK FACTORS" BEGINNING ON PAGE 6 OF THE ACCOMPANYING PROSPECTUS FOR A
DESCRIPTION OF CERTAIN FACTORS THAT SHOULD BE CONSIDERED BY PROSPECTIVE
INVESTORS.
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THESE SECURITIES HAVE NOT BEEN APPROVED OR DISAPPROVED BY THE SECURITIES AND
EXCHANGE COMMISSION OR ANY STATE SECURITIES COMMISSION NOR HAS THE SECURITIES
AND EXCHANGE COMMISSION OR ANY STATE SECURITIES COMMISSION PASSED UPON THE
ACCURACY OR ADEQUACY OF THIS PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A
CRIMINAL OFFENSE.
The date of this Prospectus Supplement is August 21, 1998.