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Prospectus Supplement No. 1 Filed Pursuant to Rule 424(b)(3)
to Prospectus Dated December 22, 1999 File No. 333-88985
CEPHALON, INC.
2,500,000 SHARES OF $3.625 CONVERTIBLE EXCHANGEABLE PREFERRED STOCK
$125,000,000 7.25% CONVERTIBLE SUBORDINATED DEBENTURES
6,975,447 SHARES OF COMMON STOCK
This prospectus supplement supplements information contained in that
certain prospectus of Cephalon, Inc. dated December 22, 1999 relating to the
potential resale from time to time of $3.625 Convertible Exchangeable Preferred
Stock, par value $.01 per share, 7.25% Convertible Subordinated Debentures (if
issued) and Common Stock issuable upon conversion of the Preferred Stock or
Debentures (if issued). This prospectus supplement is not complete without, and
may not be delivered or utilized except in connection with the prospectus,
including any amendments or supplements thereto.
The following table amends the information set forth in the prospectus
under the caption "Selling Stockholders" with respect to:
- the respective amount of shares of preferred stock
beneficially owned by each selling stockholder and
that may be sold and the percent of of outstanding
preferred stock held by such stockholder;
- the principal amount of debentures that would be
beneficially owned and may be sold by each selling
stockholder; and
- the number of shares of common stock that may be sold
by the selling stockholders pursuant to this
prospectus, as amended or supplemented.
<TABLE>
<CAPTION>
Number of
Common Shares
Number of Shares Percent of Principal Amount of Issued Upon
of Preferred Stock Outstanding Debentures Beneficially Conversion That
Name of Beneficially Preferred Owned That May Be May Be Sold
Selling Stockholder (1) Owned (2) Stock Sold
----------------------- ------------------ ----------- ----------------------- ---------------
<S> <C> <C> <C> <C>
Tribeca Investments, LLC 125,000 5% $6,250,000 348,750
</TABLE>
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(1) The information set forth herein is as of December 23, 1999 and will be
updated as required.
(2) Beneficial ownership is determined in accordance with the rules of the
SEC and generally includes voting or investment power with respect to
securities.
THE DATE OF THIS PROSPECTUS IS DECEMBER 28, 1999
