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PURSUANT TO RULE 424(b)(3)
FILE NO. 333-24385
PROSPECTUS SUPPLEMENT NO. 25
TO PROSPECTUS DATED APRIL 29, 1997
$230,000,000
5-3/4% CONVERTIBLE SUBORDINATED NOTES DUE 2004
AND
SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION THEREOF
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The Prospectus dated April 29, 1997, is hereby supplemented as follows
to restate, in its entirety, the "Selling Securityholders" section on page 26 of
the Prospectus:
SELLING SECURITYHOLDERS
The following table sets forth the name of each Selling Securityholder
and relationship, if any, with the Company and (i) except as noted below, the
amount of Convertible Notes owned by each Selling Securityholder as of March 20,
1997 (assuming no Convertible Notes have been sold under this Prospectus as of
such date), (ii) the maximum amount of Convertible Notes which may be offered
for the account of such Selling Securityholder under this Prospectus, (iii) the
amount of Common Stock owned by each Selling Securityholder as of March 20,
1997, and (iv) the maximum amount of Common Stock which may be offered for the
account of such Selling Securityholder under this Prospectus.
<TABLE>
<CAPTION>
PRINCIPAL
PRINCIPAL AMOUNT OF
AMOUNT OF CONVERTIBLE COMMON STOCK COMMON STOCK
CONVERTIBLE NOTES OFFERED OWNED PRIOR TO OFFERED
NAME OF SELLING SECURITYHOLDER NOTES OWNED ($) HEREBY ($) OFFERING (1) HEREBY (2)
- ---------------------------------------- --------------- ------------- --------------- ------------
<S> <C> <C> <C> <C>
Salomon Brothers Inc. (23) 28,025,000 28,025,000 1,180,000 1,180,000
Robertson Stephens & Co. LLP (28) 21,350,000 21,350,000 898,947 898,947
Shepherd Trading Limited (23) 10,149,000 10,149,000 427,326 427,326
Deutsche Morgan Grenfell, Inc. (21) 10,065,000 10,065,000 423,789 423,789
General Motors Employees Domestic
Group Trust(27) 10,000,000 10,000,000 421,052 421,052
Reliant Trading (23) 8,602,000 8,602,000 362,189 362,189
Lincoln National Life Insurance (5) 7,080,000 7,080,000 298,105 298,105
The NorthWestern Mutual Life Insurance
Company (18) 7,000,000 7,000,000 294,736 294,736
Smith Barney Inc. (28) 6,570,000 6,570,000 276,631 276,631
AARP Growth and Income Fund 5,700,000 5,700,000 240,000 240,000
</TABLE>
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<TABLE>
<S> <C> <C> <C> <C>
Equitable Life Assurance Separate
Account Convertibles (6) 5,645,000 5,645,000 237,684 237,684
Scudder Growth and Income Fund 5,300,000 5,300,000 223,157 223,157
OCM Convertible Trust (5) 4,095,000 4,095,000 172,421 172,421
Oregon Equity Fund (21) 4,000,000 4,000,000 168,421 168,421
NationsBanc Montgomery
Securities (22) 4,000,000 4,000,000 168,421 168,421
UBS Securities LLC (25) 4,000,000 4,000,000 168,421 168,421
Putnam Capital Appreciation Fund 3,850,000 3,850,000 162,105 162,105
Dillon, Read & Co. Inc. (9) 3,615,000 3,615,000 152,210 152,210
Shepherd Investments
International, Ltd. (17) 3,467,000 3,467,000 145,978 145,978
Stark International (17) 3,467,000 3,467,000 145,978 145,978
State of Connecticut Combined
Investment Funds (5) 3,095,000 3,095,000 130,315 130,315
Goldman, Sachs & Co. (29) 3,076,000 3,076,000 129,515 129,515
Credit Suisse First Boston
Corporation (15) 3,000,000 3,000,000 126,315 126,315
SAIF Corporation 3,000,000 3,000,000 126,315 126,315
Surfboard and Co. (25) 3,000,000 3,000,000 126,315 126,315
SB/Travelers Vintage Alliance
Growth (5) 2,905,000 2,905,000 122,315 122,315
BT Alex.Brown Inc. (25) 2,900,000 2,900,000 122,105 122,105
Lincoln National Convertible
Securities Fund (5) 2,695,000 2,695,000 113,473 113,473
Daiwa Europe LTD (9) 2,500,000 2,500,000 105,263 105,263
MainStay Convertible Fund (23) 2,500,000 2,500,000 105,263 105,263
Millennium Trading Co. (14) 2,475,000 2,475,000 104,210 104,210
Delta Air Lines Master Trust (5) 2,380,000 2,380,000 100,210 100,210
Vanguard Convertible Securities
Fund, Inc. (5) 2,235,000 2,235,000 94,105 94,105
Hudson River Trust Balanced Fund (6) 2,245,000 2,245,000 94,526 94,526
Memphis Light, Gas & Water
Retirement Fund (6) 2,230,000 2,230,000 93,894 93,894
Forum Capital Markets LP (13) 2,255,000 2,255,000 94,947 94,947
Natwest Markets (19) 2,000,000 2,000,000 84,210 84,210
Hudson River Trust Growth & Income
Fund (6) 1,830,000 1,830,000 77,052 77,052
Hudson River Trust Growth
Investors (6) 1,790,000 1,790,000 75,368 75,368
Columbia/HCA Money Purchase
Plan (6) 1,685,000 1,685,000 70,947 70,947
Aragon Investmens (20) 1,600,000 1,600,000 67,368 67,368
New York Life Separate
Account #7 (23) 1,500,000 1,500,000 63,157 63,157
Taft Securities LLC (20) 1,400,000 1,400,000 58,947 58,947
Pension Reserves Investment
Management Board 1,325,000 1,325,000 55,789 55,789
</TABLE>
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<TABLE>
<S> <C> <C> <C> <C>
BNP Arbitrage SNC (10) 1,275,000 1,275,000 53,684 53,684
San Diego County 1,265,000 1,265,000 53,263 53,263
Franklin Universal Trust (16) 1,250,000 1,250,000 52,631 52,631
Hughes Aircraft Company Master
Retirement Trust (5) 1,235,000 1,235,000 52,000 52,000
Arkansas P.E.R.S. 1,200,000 1,200,000 50,526 50,526
VIP Growth Fund (5) 1,195,000 1,195,000 50,315 50,315
Bear Stearns & Co. Inc. (19) 1,025,000 1,025,000 43,157 43,157
State of Delaware - Froley, Revy 1,020,000 1,020,000 42,947 42,947
Lehman Brothers International
Europe (14) 1,000,000 1,000,000 42,105 42,105
SAFECO High Yield Bond Fund (24) 1,000,000 1,000,000 42,105 42,105
Baird, Patrick & Co. Inc. (25) 1,000,000 1,000,000 42,105 42,105
State Employees' Retirement Fund
of the State of Delaware (5) 970,000 970,000 40,842 40,842
Nicholas-Applegate Income &
Growth Fund 958,000 958,000 40,336 40,336
Thermo Electron Balanced Investment Fund (26) 850,000 850,000 35,789 35,789
Weirton Trust (5) 815,000 815,000 34,315 34,315
The Hotel Union and Industry of
Hawaii (6) 735,000 735,000 30,947 30,947
The J.W. McConnell Family Foundation (26) 630,000 630,000 26,526 26,526
Winchester Convertible Plus, Ltd. (8) 600,000 600,000 25,263 25,263
Donaldson, Lufkin & Jenrette Securities
Corp. (15) 500,000 500,000 21,052 21,052
Pacific Life Insurance Company (22) 500,000 500,000 21,052 21,052
MainStay Strategic Income Fund (23) 500,000 500,000 21,052 21,052
Brown & Williamson Tobacco Corp.
Master Retirement Trust (23) 500,000 500,000 21,052 21,052
The Frist Foundation (6) 575,000 575,000 24,210 24,210
McMahan Securities Co., L.P. (16) 489,000 489,000 20,589 20,589
Susquehanna Capital Group (9) 485,000 485,000 20,421 20,421
ICI American Holdings
Pension Trust 410,000 410,000 17,263 17,263
Zeneca Holdings Pension Trust 410,000 410,000 17,263 17,263
Highbridge Capital Corporation (23) 400,000 400,000 16,842 16,842
Equitable Life Assurance Separate
Account Balanced (6) 380,000 380,000 16,000 16,000
Walker Art Center (5) 315,000 315,000 13,263 13,263
Starvest Discretionary Portfolio 300,000 300,000 12,631 12,631
San Diego City Retirement 297,000 297,000 12,505 12,505
First Church of Christ Scientist
Endowment (26) 270,000 270,000 11,368 11,368
J.M. Hull Associates, L.P. 250,000 250,000 10,526 10,526
The Hotel Union - ILWU Pension
Trust (6) 250,000 250,000 10,526 10,526
</TABLE>
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<TABLE>
<S> <C> <C> <C> <C>
Christian Science Trustees for Gifts
and Endowments (26) 250,000 250,000 10,526 10,526
Partner Reinsurance Company,
Limited (5) 240,000 240,000 10,105 10,105
Wake Forest University 236,000 236,000 9,936 9,936
Kapiolani Medical Center 200,000 200,000 8,421 8,421
David Lipscomb University General
Endowment (5) 175,000 175,000 7,368 7,368
Engineers Joint Pension Fund 150,000 150,000 6,315 6,315
Foundation Account No. 1 (8) 150,000 150,000 6,315 6,315
Collective Convertible Bond Fund (18) 150,000 150,000 6,315 6,315
Nalco Chemical Co. Retirement
Trust 135,000 135,000 5,684 5,684
United National Life Insurance (5) 135,000 135,000 5,684 5,684
Austin Firefighters 109,000 109,000 4,589 4,589
Retirement Plan for Pilots of
Hawaiian Airlines, Inc. 100,000 100,000 4,210 4,210
Franklin Strategic Income Fund (16) 100,000 100,000 4,210 4,210
Franklin Multi-Income Trust (16) 100,000 100,000 4,210 4,210
Baptist Hospital 95,000 95,000 4,000 4,000
Occidental College 90,000 90,000 3,789 3,789
Boston Museum of Fine Arts 40,000 40,000 1,684 1,684
Dunham & Associates Fund II 7,000 7,000 294 294
Dunham & Associates Ser. II 3,000 3,000 126 126
Delaware Group Dividend &
Income Fund, Inc. 1,000 1,000 42 42
Total(3) 238,921,000 238,921,000 10,059,788 10,059,788
</TABLE>
(1) Comprises the shares of Common Stock into which the Convertible Notes
held by such Selling Securityholder are convertible at the initial
conversion rate. The Conversion Rate and the number of shares of Common
Stock issuable upon conversion of the Convertible Notes are subject to
adjustment under certain circumstances. See "Description of Convertible
Notes -- Conversion." Accordingly, the number of shares of Common Stock
issuable upon conversion of the Convertible Notes may increase or
decrease from time to time.
(2) Assumes conversion into Common Stock of the full amount of Convertible
Notes held by the Selling Securityholder at the initial conversion rate
and the offering of such shares by such Selling Securityholder pursuant
to this Prospectus. The Conversion Rate and the number of shares of
Common Stock issuable upon conversion of the Convertible Notes is
subject to adjustment under certain circumstances. See "Description of
Convertible Notes -- Conversion." Accordingly, the number of shares of
Common Stock issuable upon conversion of the Convertible Notes may
increase or decrease from time to time. Fractional shares will not be
issued upon conversion of the Convertible Notes; rather, cash will be
paid in lieu of fractional shares, if any.
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(3) No such holder may offer Convertible Notes pursuant to this Prospectus
until such holder is included as a Selling Securityholder in a
supplement to this Prospectus in accordance with the Registration
Agreement (as defined). Amount indicated may be in excess of the total
amount registered due to sales or transfers subsequent to the different
dates as of which the information in this table has been compiled.
(4) Assumes that the unnamed holders of Convertible Notes or any future
transferees, pledgees, donees or successors of or from any such unnamed
holder do not beneficially own any Common Stock other than the Common
Stock issuable upon conversion of the Convertible Notes at the initial
conversion rate.
(5) The amount of Convertible Notes owned by each Selling Securityholder as
of May 6, 1997 (assuming no Convertible Notes have been sold under this
Prospectus as of such date).
(6) The amount of Convertible Notes owned by each Selling Securityholder as
of May 15, 1997 (assuming no Convertible Notes have been sold under
this Prospectus as of such date).
(7) The amount of Convertible Notes owned by each Selling Securityholder as
of May 23, 1997 (assuming no Convertible Notes have been sold under
this Prospectus as of such date).
(8) The amount of Convertible Notes owned by each Selling Securityholder as
of June 2, 1997 (assuming no Convertible Notes have been sold under
this Prospectus as of such date.)
(9) The amount of Convertible Notes owned by each Selling Securityholder as
of June 10, 1997 (assuming no Convertible Notes have been sold under
this Prospectus as of such date).
(10) The amount of Convertible Notes owned by each Selling Securityholder as
of June 17, 1997 (assuming no Convertible Notes have been sold under
this Prospectus as of such date).
(11) The amount of Convertible Notes owned by each Selling Securityholder as
of June 30, 1997 (assuming no Convertible Notes have been sold under
this Prospectus as of such date).
(12) The amount of Convertible Notes owned by each Selling Securityholder as
of July 7, 1997 (assuming no Convertible Notes have been sold under
this Prospectus as of such date).
(13) The amount of Convertible Notes owned by each Selling Securityholder as
of July 21, 1997 (assuming no Convertible Notes have been sold under
this Prospectus as of such date).
(14) The amount of Convertible Notes owned by each Selling Securityholder as
of August 1, 1997 (assuming no Convertible Notes have been sold under
this Prospectus as of such date).
(15) The amount of Convertible Notes owned by each Selling Securityholder as
of August 8, 1997 (assuming no Convertible Notes have been sold under
this Prospectus as of such date).
(16) The amount of Convertible Notes owned by each Selling Securityholder as
of August 28, 1997 (assuming no Convertible Notes have been sold under
this Prospectus as of such date).
(17) The amount of Convertible Notes owned by each Selling Securityholder as
of September 10, 1997 (assuming no Convertible Notes have been sold
under this Prospectus as of such date).
(18) The amount of Convertible Notes owned by each Selling Securityholder as
of September 24, 1997 (assuming no Convertible Notes have been sold
under this Prospectus as of such date).
(19) The amount of Convertible Notes owned by each Selling Securityholder as
of October 7, 1997 (assuming no Convertible Notes have been sold under
this Prospectus as of such date).
(20) The amount of Convertible Notes owned by each Selling Securityholder as
of October 17, 1997 (assuming no Convertible Notes have been sold under
this Prospectus as of such date).
(21) The amount of Convertible Notes owned by each Selling Securityholder as
of October 28, 1997 (assuming no Convertible Notes have been sold under
this Prospectus as of such date).
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(22) The amount of Convertible Notes owned by each Selling Securityholder as
of November 12, 1997 (assuming no Convertible Notes have been sold
under this Prospectus as of such date).
(23) The amount of Convertible Notes owned by each Selling Securityholder as
of December 11, 1997 (assuming no Convertible Notes have been sold
under this Prospectus as of such date).
(24) The amount of Convertible Notes owned by each Selling Securityholder as
of February 26, 1998 (assuming no Convertible Notes have been sold
under this Prospectus as of such date).
(25) The amount of Convertible Notes owned by each Selling Securityholder as
of March 11, 1998 (assuming no Convertible Notes have been sold under
this Prospectus as of such date).
(26) The amount of Convertible Notes owned by each Selling Securityholder as
of April 30, 1998 (assuming no Convertible Notes have been sold under
this Prospectus as of such date).
(27) The amount of Convertible Notes owned by each Selling Securityholder
as of May 15, 1998 (assuming no Convertible Notes have been sold under
this Prospectus as of such date).
(28) The amount of Convertible Notes owned by each Selling Securityholder
as of June 24, 1998 (assuming no Convertible Notes have been sold under
this Prospectus as of such date).
(29) The amount of Convertible Notes owned by each Selling Securityholder
as of June 30, 1998 (assuming no Convertible Notes have been sold under
this Prospectus as of such date).
Because the Selling Securityholders may, pursuant to this Prospectus,
offer all or some portion of the Convertible Notes and Common Stock they
presently hold or, with respect to Common Stock, have the right to acquire upon
conversion of such Convertible Notes, no estimate can be given as to the amount
of the Convertible Notes and Common Stock that will be held by the Selling
Securityholders upon termination of any such sales. In addition, the Selling
Securityholders identified above may have sold, transferred or otherwise
disposed of all or a portion of their Convertible Notes and Common Stock since
the date on which they provided the information regarding their Convertible
Notes and Common Stock, in transactions exempt from the registration
requirements of the Securities Act. See "Plan of Distribution."
Only Selling Securityholders identified above who beneficially own the
Convertible Notes and Common Stock set forth opposite each such Selling
Securityholder's name in the foregoing table on the effective date of the
Registration Statement may sell such Convertible Notes and Common Stock pursuant
to this Prospectus. The Company may from time to time, in accordance with the
Registration Agreement, include additional Selling Securityholders in
supplements to this Prospectus.
Other than as set forth in the table, none of the Selling
Securityholders listed above had any material relationship with the Company
other than as a result of ownership of the Convertible Notes, within the
three-year period ending on the date of this Prospectus.
The Company will pay the expenses of registering the Convertible Notes
and Common Stock being sold hereunder.
The date of this Prospectus Supplement No. 25 is June 30, 1998.
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