<PAGE> 1
FILED PURSUANT TO RULE 424(B)(3)
REGISTRATION NO. 333-53457
SENSORMATIC ELECTRONICS CORPORATION
SUPPLEMENT NUMBER FOUR TO PROSPECTUS DATED DECEMBER 20, 1999
This Supplement is a part of the Prospectus dated December 20,
1999 relating to 6,900,000 Depositary Shares ("Depositary Shares"), each
representing a one-tenth interest in a share of 6 1/2% Convertible Preferred
Stock, par value $.01 per share ("Preferred Stock"), of Sensormatic Electronics
Corporation ("Sensormatic"). The Prospectus (as well as this Supplement) also
relates to 690,000 shares of the Preferred Stock and certain shares of Common
Stock, par value $.01 per share, of Sensormatic, issued upon conversion of such
Depositary Shares and/or Preferred Stock and issued or issuable in payment of
dividends and certain premium payments with respect to the Preferred Stock. The
Prospectus was previously supplemented by Supplement Number One dated January
24, 2000, Supplement Number Two dated January 25, 2000, Supplement Number Three
dated February 15, 2000 and Supplement Number Four dated April 6, 2000. Defined
terms contained in this Supplement have the meanings assigned to them in the
Prospectus.
The following updates certain information concerning the
Selling Securityholders and the securities of Sensormatic held by them, as set
forth in the Prospectus under the caption "Selling Security Holders", based on
information received from the Selling Securityholders named below after the date
of the Prospectus and prior to the date hereof. The information concerning the
Selling Securityholders in the Prospectus (including any previous Supplement) is
not being updated to show sales, except to the extent that any such sales are
reflected in the current beneficial ownership information set forth below.
Except as amended or supplemented hereby or as contemplated by the preceding
sentence, the information in the Prospectus concerning the Selling
Securityholders and the securities of Sensormatic held by them, as previously
amended by any Supplements previously filed, remains in full force and effect.
<TABLE>
<CAPTION>
COMMON STOCK DEPOSITARY SHARES
------------------------------------------- --------------------------------------------------
BENE- BENE-
FICIALLY FICIALLY
OWNED OWNED
BENEFICIALLY OWNED AFTER AFTER
PRIOR TO THIS OFFERED FOR THIS BENEFICIALLY OWNED PRIOR OFFERED FOR THIS
NAME OF SELLING SECURITYHOLDER OFFERING SALE OFFERING TO THIS OFFERING SALE OFFERING
- ------------------------------ ------------------ ----------- -------- ------------------------- ----------- --------
NO. OF % OF
NO. OF % OF DEPOSITARY DEPOSITARY
SHARES SHARES SHARES SHARES
--------- ------ ----------- -----------
<S> <C> <C> <C> <C> <C> <C> <C> <C>
Deutsche Bank Securities(1) 3,485,245 * 3,485,245 0 2,348,676 34 2,348,676 0
--------- --- --------- --- --------- --- --------- ---
Total 3,485,245 * 3,485,245 0 2,348,676 34 2,348,676 0
========= === ========= === ========= === ========= ===
<CAPTION>
6 1/3% CONVERTIBLE PREFERRED STOCK
-------------------------------------------------
BENEFICIALLY
BENEFICIALLY OWNED OWNED
NAME OF SELLING SECURITYHOLDER PRIOR TO THIS OFFERING AFTER THIS
- ------------------------------ ----------------------- OFFERING
NO. OF ------------
SHARES OF % OF
PREFERRED PREFERRED
STOCK STOCK
---------- ----------
<S> <C> <C> <C> <C>
Deutsche Bank Securities(1) 235,868 34 234,868 0
------- --- ------- ---
Total 345,868 34 234,868 0
======= === ======= ===
</TABLE>
(1) The information in this Supplement reflects the current beneficial
ownership information for this Selling Securityholder as of the date of
this filing and accordingly amends and supersedes the information
concerning this Selling Securityholder in the Prospectus or any
Supplement thereto filed prior to the date of this Supplement.
THE DATE OF THIS SUPPLEMENT IS MAY 10, 2000
