<PAGE>
PROSPECTUS SUPPLEMENT FILED PURSUANT TO RULE 424(b)(3)
(TO PROSPECTUS DATED REGISTRATION NO. 333-36958
JUNE 28, 2000)
SEPRACOR INC.
$460,000,000
PRINCIPAL AMOUNT OF 5% CONVERTIBLE
SUBORDINATED DEBENTURES DUE 2007
------------------------
4,979,432 SHARES OF COMMON STOCK,
$0.10 PAR VALUE PER SHARE
------------------------
The information in this prospectus supplement concerning the Selling
Securityholders supplements the statements set forth under the caption "Selling
Securityholders" in the prospectus. Capitalized items used and not defined
herein shall have the meanings given to them in the prospectus. The information
set forth under the caption "Selling Securityholders" in the prospectus is
supplemented as follows:
SELLING SECURITYHOLDERS
We originally sold the debentures on February 14, 2000 to Deutsche Banc
Securities, Inc. The initial purchaser of the debentures has advised us that the
debentures were resold in transactions exempt from the registration requirements
of the Securities Act to (1) "qualified institutional buyers," as defined in
Rule 144A of the Securities Act, and (2) outside the United States to certain
non-United States person in reliance on Regulation S of the Securities Act.
These subsequent purchasers, or their transferees, pledgees, donees or
successors, may from time to time offer and sell any or all of the debentures
and/or shares of the common stock issuable upon conversion of the debentures
pursuant to this prospectus.
The debentures and the shares of common stock issuable upon conversion of
the debentures have been registered in accordance with to the registration
rights agreement. Pursuant to the registration rights agreement, we are required
to file a registration statement with regard to the debentures and the shares of
our common stock issuable upon conversion of the debentures and to keep the
registration statement effective until the earlier of:
(1) the sale of all the securities registered pursuant to the
registration rights agreement and
(2) the expiration of the holding period applicable to these securities
under Rule 144(k) under the Securities Act or any successor
provision.
The selling securityholders may choose to sell debentures and/or the shares
of common stock issuable upon conversion of the debentures from time to time.
See "Plan of Distribution."
The following table sets forth:
(1) the name of each selling securityholder who has provided us with
notice as of the date of this prospectus pursuant to the registration
rights agreement of their intent to sell or otherwise dispose of
debentures and/or shares of common stock issuable upon conversion of
the debentures pursuant to the registration statement,
(2) the principal amount of debentures and the number of shares of our
common stock issuable upon conversion of the debentures which they
may sell from time to time pursuant to the registration statement,
and
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(3) the amount of outstanding debentures and our common stock
beneficially owned by the selling securityholder prior to the
offering, assuming no conversion of the debentures.
To our knowledge, no selling securityholder nor any of its affiliates has
held any position or office with, been employed by or otherwise has had any
material relationship with us or our affiliates, during the three years prior to
the date of this prospectus.
A selling securityholder may offer all or some portion of the debentures and
shares of the common stock issuable upon conversion of the debentures.
Accordingly, no estimate can be given as to the amount or percentage of
debentures or our common stock that will be held by the selling securityholders
upon termination of sales pursuant to this prospectus. In addition, the selling
securityholders identified below may have sold, transferred or disposed of all
or a portion of their debentures since the date on which they provided the
information regarding their holdings in transactions exempt from the
registration requirements of the Securities Act.
The information contained under the column heading "Shares That May be Sold"
assumes conversion of full amount of the debentures held by the holder at the
initial rate of $92.38 in principal amount of the debentures per share of the
common stock.
<TABLE>
<CAPTION>
AMOUNT OF 5% SHARES OF
AMOUNT OF 5% DEBENTURES COMMON STOCK
DEBENTURES THAT OWNED BEFORE SHARES THAT MAY OWNED BEFORE
NAME MAY BE SOLD OFFERING BE SOLD OFFERING
---- --------------- ------------ --------------- ------------
<S> <C> <C> <C> <C>
ABN AMRO Incorporated................. $ 4,250,000 4,250,000 46,005 0
AIG/National Union Fire Insurance..... 600,000 600,000 6,494 20,055(1)
Alexandra Global Investment Fund I
Ltd................................. 4,000,000 4,000,000 43,299 0
Allstate Insurance Company............ 1,850,000 1,850,000 20,025 91,627(2)
Alta Partners Holdings, LDC........... 3,000,000 3,000,000 32,474 0
Argent Classic Convertible Arbitrage
Fund................................ 3,000,000 3,000,000 32,474 0
Argent Convertible Arbitrage Fund
Ltd................................. 1,000,000 1,000,000 10,824 0
Aristeia International Ltd............ 5,000,000 5,000,000 54,124 0
Aristeia Trading, L.P................. 3,000,000 3,000,000 32,474 0
Bank Austria Cayman Island, Ltd....... 3,000,000 3,000,000 32,474 0
Bear, Stearns & Co. Inc............... 3,500,000 3,500,000 37,886 64,064(2)
Black Diamond Offshore, Ltd........... 1,344,000 1,344,000 14,548 0
BNP Arbitrage SNC..................... 10,312,000 10,312,000 111,625 0
BNP Cooper Neff Convertible Strategies
Fund, L.P........................... 688,000 688,000 7,447 0
Boulder II Limited.................... 9,500,000 9,500,000 102,836 70,470(2)
Chrysler Corporation Master Retirement
Trust............................... 3,385,000 3,385,000 36,642 0
CIBC World Markets.................... 8,000,000 8,000,000 86,598 0
CIBC World Markets International
Arbitrage Corp...................... 32,000,000 32,000,000 346,395 0
Clinton Riverside Convertible
Portfolio Limited................... 4,000,000 4,000,000 43,299 0
Credit Suisse First Boston
Corporation......................... 5,000,000 5,000,000 54,124 0
Deephaven Domestic Convertible Trading
Ltd................................. 4,410,000 4,410,000 47,737 0
Delaware PERS......................... 1,600,000 1,600,000 17,319 0
Delphi Foundation, Inc................ 60,000 60,000 649 0
Deutsche Bank Securities.............. 184,025,000 184,025,000 1,992,043 0
</TABLE>
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<TABLE>
<CAPTION>
AMOUNT OF 5% SHARES OF
AMOUNT OF 5% DEBENTURES COMMON STOCK
DEBENTURES THAT OWNED BEFORE SHARES THAT MAY OWNED BEFORE
NAME MAY BE SOLD OFFERING BE SOLD OFFERING
---- --------------- ------------ --------------- ------------
<S> <C> <C> <C> <C>
Diversifvied Arbitrage................ 250,000 250,000 2,706 0
Double Black Diamond Offshore, LDC.... 4,315,000 4,315,000 46,709 0
Fidelity Financial Trust:
Fidelity Convertible Securities
Fund(4)............................. 2,000,000 2,000,000 21,649 0
Forest Alternative Strategies Fund II
L.P. A5M............................ 700,000 700,000 7,577 0
Forest Fulcrum Fund LP................ 5,800,000 5,800,000 62,784 0
Forest Global Convertible Fund........ 20,165,000 20,165,000 218,283 0
Forest Performance Fund L.P........... 1,800,000 1,800,000 19,484 0
Gaia Offshore Master Fund Ltd......... 1,500,000 1,500,000 16,237 0
General Motors Arbitrage.............. 250,000 250,000 2,706 0
General Motors Employee Global Group
Pension Trust....................... 8,784,000 8,784,000 95,085 0
General Motors Foundation............. 528,000 528,000 5,715 0
General Motors LT..................... 250,000 250,000 2,706 0
Goldman Sachs and Company............. 2,370,000 2,370,000 25,654 0
Grace Brothers, Ltd................... 2,000,000 2,000,000 21,649 0
Granville Capital Corporation......... 7,500,000 7,500,000 81,186 116,475(1)(2)
Highbridge International.............. 7,500,000 7,500,000 81,186 0
ICI American Holdings................. 850,000 850,000 9,201 0
Island Holdings....................... 30,000 30,000 324 422(1)
Jeffries & Co......................... 10,000,000 10,000,000 108,248 0
JMG Capital Partners, L.P............. 2,750,000 2,750,000 29,768 0
KBC Financial Products................ 6,000,000 6,000,000 64,949 0
LDG Limited........................... 425,000 425,000 4,600 27,916(1)(2)
Lehman Brothers Inc................... 2,300,000 2,300,000 24,897 188,988(2)
LLT Limited........................... 2,200,000 2,200,000 23,814 0
Luxor Master Fund..................... 1,860,000 1,860,000 20,134 0
Lyxor Master Fund Trust............... 500,000 500,000 5,412 0
Merrill Lynch, Pierce, Fenner and
Smith Inc........................... 2,250,000 2,250,000 24,355 21,973(2)
Morgan Stanley & Co................... 6,000,000 6,000,000 64,949 0
Motion Picture Industry Health Plan--
Active Member Fund.................. 705,000 705,000 7,631 0
Motion Picture Industry Health Plan--
Retiree Member Fund................. 355,000 355,000 3,842 0
Motors Insurance Corporation.......... 2,628,000 2,628,000 28,447 0
Nalco Chemical Company................ 225,000 225,000 2,435 7,607(2)
Nomura Securities International
Inc................................. 7,000,000 7,000,000 75,773 75,500
OCM Convertible Trust................. 2,995,000 2,995,000 32,420 0
Onex Industrial Partners Ltd.......... 1,500,000 1,500,000 16,237 49,649(2)
Oppenheimer Convertible Securities
Fund................................ 5,000,000 5,000,000 54,124 0
Partner Reinsurance Company Ltd....... 430,000 430,000 4,654 0
Pebble Capital Inc.................... 1,000,000 1,000,000 10,824 14,286(2)
Q Investments, L.P.................... 3,000,000 3,000,000 32,474 24,024(2)
R2 Investments, LDC................... 7,000,000 7,000,000 75,773 56,356(3)
Sage Capital.......................... 3,000,000 3,000,000 32,474 0
</TABLE>
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<TABLE>
<CAPTION>
AMOUNT OF 5% SHARES OF
AMOUNT OF 5% DEBENTURES COMMON STOCK
DEBENTURES THAT OWNED BEFORE SHARES THAT MAY OWNED BEFORE
NAME MAY BE SOLD OFFERING BE SOLD OFFERING
---- --------------- ------------ --------------- ------------
<S> <C> <C> <C> <C>
Salomon Brothers Asset Management
Inc................................. 4,000,000 4,000,000 43,299 0
Silvercreek Limited Partnership....... 2,000,000 2,000,000 21,649 33,761(2)
Spear, Leeds & Kellogg................ 1,000,000 1,000,000 10,824 0
Starvest Combined Portfolio........... 700,000 700,000 7,577 11,610(1)
State Employees' Retirement Fund of
the State of Delaware............... 3,070,000 3,070,000 33,232 0
State of Connecticut Combined
Investment Fund..................... 7,175,000 7,175,000 77,668 0
State of Oregon Equity................ 5,100,000 5,100,000 55,206 0
TCW Group, Inc........................ 29,600,000 29,600,000 320,415 0
TQA Master Plus Fund, Ltd............. 1,750,000 1,750,000 18,943 0
TQA Master Fund, Ltd.................. 1,750,000 1,750,000 18,943 0
Transamerica Life Insurance and
Annuity Company..................... 15,000,000 15,000,000 162,372 80,080(2)
Transamerica Occidental Life Insurance
Company............................. 5,000,000 5,000,000 54,124 0
Tribeca Investments LLC............... 15,000,000 15,000,000 162,372 0
Trusco Capital Management............. 3,000,000 3,000,000 32,474 24,947(2)
Vanguard Convertible Securities Fund,
Inc................................. 6,730,000 6,730,000 72,851 0
White River Securities LLC............ 3,500,000 3,500,000 37,886 0
Worldwide Transactions, Ltd........... 341,000 341,000 3,691 2,642(2)
Zeneca Holdings Trust................. 650,000 650,000 7,036 0
Zurich HFR Master Hedge Fund.......... 100,000 100,000 1,082 0
</TABLE>
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(1) Assumes conversion of the full amount of 6.25% convertible subordinated
debentures due 2005 held by the holder at the rate of $23.6845 in principal
amount of the debentures per share of the common stock.
(2) Assumes conversion of the full amount of 7% convertible subordinated
debentures due 2005 held by the holder at the rate of $62.4375 in principal
amount of the debentures per share of the common stock.
(3) Assumes conversion of $3,500,000 of 7% convertible subordinated debentures
due 2005 held by R2 Investments, LDC at the rate of $62.4375 in principal
amount of the debentures per share of the common stock.
(4) The entity is either an investment company or a portfolio of an investment
company registered under Section 8 of the Investment Company Act of 1940, as
amended, or a private investment account advised by Fidelity Management &
Research Company ("FMR Co."). FMR Co. is a Massachusetts corporation and an
investment advisor registered under Section 203 of the Investment Advisors
Act of 1940, as amended, and provides investment advisory services to each
of such Fidelity entities identified above, and to other registered
investment companies and to certain other funds which are generally offered
to a limited group of investors. FMR Co. is a wholly-owned subsidiary of FMR
Corp., a Massachusetts corporation.
The date of this Prospectus Supplement is October 23, 2000.
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