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Prospectus Supplement No. 10 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, as amended and
supplemented from time to time, 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 supplements, or amends, as noted, 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 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 (3)
Selling Stockholder (1) Owned (2) Stock Sold
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<S> <C> <C> <C> <C>
The following information supplements the
information set forth in the prospectus
originally filed or as previously amended
or supplemented:
THE KAUFMANN FUND........................... 95,000 3.8% 4,750,000 265,050
MERRILL LYNCH INTERNATIONAL ................ 35,000 1.4% 1,750,000 97,650
</TABLE>
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(1) The information set forth herein is as of April 6, 2000 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.
(3) Assume conversion of preferred stock at an initial conversion price of
$17.92 per share.
THE DATE OF THIS PROSPECTUS IS APRIL 10, 2000
