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PURSUANT TO RULE 424(B)(3)
FILE NO. 333-24385
PROSPECTUS SUPPLEMENT NO. 13
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.(14)............ 20,025,000 20,025,000 843,158 843,158
Robertson Stephens & Co. LLP(16)...... 7,500,000 7,500,000 315,789 315,789
Shepherd Trading Limted(17)........... 7,524,000 7,524,000 316,800 316,800
Lincoln National Life Insurance(5).... 7,080,000 7,080,000 298,105 298,105
Reliant Trading(17)................... 5,977,000 5,977,000 251,663 251,663
AARP Growth and Income Fund........... 5,700,000 5,700,000 240,000 240,000
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
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
Oregon Equity Fund.................... 3,500,000 3,500,000 147,368 147,368
State of Connecticut Combined
Investment Funds(5)................. 3,095,000 3,095,000 130,315 130,315
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
SB/Travelers Vintage Alliance
Growth(5)........................... 2,905,000 2,905,000 122,315 122,315
Shepherd Investments International
Ltd.(17).............................. 2,842,000 2,842,000 119,663 119,663
Stark International(17)............... 2,842,000 2,842,000 119,663 119,663
Lincoln National Convertible
Securities Fund(5).................. 2,695,000 2,695,000 113,473 113,473
Daiwa Eurpoe Ltd.(9).................. 2,500,000 2,500,000 105,263 105,263
Millennium Trading Co.(14)............. 2,745,000 2,475,000 104,210 104,210
Delta Air Lines Master Trust(5)....... 2,380,000 2,380,000 100,210 100,210
</TABLE>
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<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>
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
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
Pension Reserves Investment Management
Board............................... 1,325,000 1,325,000 55,789 55,789
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
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
Montgomery Securities(12)............. 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
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
Shepherd Investments International,
Ltd.(5)............................. 625,000 625,000 26,315 26,315
Stark International(5)................ 625,000 625,000 26,315 26,315
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
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
Smith Barney Inc.(17)................. 450,000 450,000 18,947 18,947
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
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
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
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
Nalco Chemical Co. Retirement Trust... 135,000 135,000 5,684 5,684
</TABLE>
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<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>
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
Subtotal.............................. 146,085,000 146,085,000 6,150,917 6,150,917
Unnamed holders of Convertible Notes
or any future transferees, pledgees,
donees or successors of or from any
such unnamed holders(3)............. $ 83,915,000 $ 83,915,000 3,533,293 3,533,293
Total....................... $ 230,000,000 $ 230,000,000 9,684,210 9,684,210
</TABLE>
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(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.
(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).
(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).
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. 13 IS September 10, 1997.
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