<PAGE>
PROSPECTUS SUPPLEMENT DATED OCTOBER 8, 1999 FILED PURSUANT TO RULE 424(b)(3)
(To Prospectus Dated October 1, 1999) SEC FILE NO. 333-84661
$100,000,000
ITC/\DeltaCom
4 1/2% Convertible Subordinated Notes Due 2006
This prospectus supplement relates to resales by the holders of ITC/\DeltaCom,
Inc.'s 4 1/2% Convertible Subordinated Notes due 2006 and the shares of
ITC/\DeltaCom's common stock, par value $.01 per share, issuable upon conversion
of the notes. This prospectus supplement should be read in conjunction with the
prospectus dated October 1, 1999, which is to be delivered with this prospectus
supplement.
The information appearing under the heading "Selling Holders" in the
prospectus is superseded in part by the information included in the table below.
Information in the table is as of September 30, 1999, except as otherwise
indicated in footnote 6:
<TABLE>
<CAPTION>
Principal
Amount of
Notes Principal
Beneficially Amount of Common
Owned Prior Notes Stock Owned Common
to the Offered Prior to the Stock Offered
Name Offering Hereby Offering(1) Hereby(2)
---- ------------- ---------- ------------ -------------
<S> <C> <C> <C> <C>
Bear Stearns & Co........... $ 1,375,000 $ 1,375,000 51,556 51,556
White River
Securities LLC............. $ 1,375,000 $ 1,375,000 51,556 51,556
JMG Convertible
Investments, L.P.......... $ 1,250,000 $ 1,250,000 46,869 46,869
Triton Capital
Investments, Ltd.......... $ 5,250,000 $ 5,250,000 196,850 196,850
Greyhound Lines............ $ 100,000 $ 100,000 3,749 3,749
LDG Limited................ $ 150,000 $ 150,000 5,624 5,624
TQA Leverage
Fund, L.P................ $ 500,000 $ 500,000 18,747 18,747
TQA Vantage
Fund, Ltd................ $ 1,000,000 $ 1,000,000 37,495 37,495
TQA Vantage Plus
Fund, Ltd................ $ 350,000 $ 350,000 13,123 13,123
BankAmerica Pension
Plan...................... $ 1,000,000 $ 1,000,000 37,495 37,495
Duckbill & Co.............. $ 1,500,000 $ 1,500,000 56,242 56,242
Employee Benefit
Convertible Securities
Fund...................... $ 225,000 $ 225,000 8,436 8,436
Nations Capital
Income Fund.............. $ 3,550,000 $ 3,550,000 133,108 133,108
Pacific Innovations Trust
Capital Income Fund....... $ 225,000 $ 225,000 8,436 8,436
</TABLE>
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<TABLE>
<CAPTION>
Principal
Amount of
Notes Principal
Beneficially Amount of Common
Owned Prior Notes Stock Owned Common
to the Offered Prior to the Stock Offered
Name Offering Hereby Offering(1) Hereby(2)
---- ------------- ---------- ------------ -------------
<S> <C> <C> <C> <C>
Forest Global Convertible
Fund Series A-5............ $ 6,850,000 $ 6,850,000 256,842 256,842
Sylvan IMA Ltd. c/o Forest
Investment Management LLC.. $ 750,000 $ 750,000 28,121 28,121
Forest Performance Fund..... $ 135,000 $ 135,000 5,061 5,061
Forest Alternative
Strategies Fund II LP
Series A 5 M............... $ 100,000 $ 100,000 3,749 3,749
Forest Alternative
Strategies Fund II LP
Series A 5 I............... $ 260,000 $ 260,000 9,748 9,748
Forest Fulcrum Fund LP...... $ 3,720,000 $ 3,720,000 139,482 139,482
Morgan Stanley Dean
Witter(3)(6)............... $ 12,250,000 $ 12,250,000 459,317 459,317
Bankers Trust, Trustee for
Chrysler Corp. Emp #1
Pension Plan dated
4/1/89(6).................. $ 1,439,000 $ 1,439,000 53,955 53,955
Chase Manhattan N.A.,
Trustee for IBM Retirement
Plan dated 12/18/45(6)...... $ 1,957,000 $ 1,957,000 73,378 73,378
State Street Bank, Custodian
for GE Pension Trust(6)..... $ 762,000 $ 762,000 28,571 28,571
Franklin & Marshall
College(6).................. $ 110,000 $ 110,000 4,124 4,124
Penn Treaty Network America
Insurance Company(6)........ $ 96,000 $ 96,000 3,599 3,599
Value Line Convertible
Fund, Inc................... $ 500,000 $ 500,000 18,747 18,747
Alexandra Global Investment
Fund I Ltd.................. $ 3,000,000 $ 3,000,000 112,485 112,485
Partner Reinsurance
Company, Ltd............... $ 350,000 $ 350,000 13,123 13,123
LLT Limited................. $ 180,000 $ 180,000 6,749 6,749
Conseco Senior Health
Insurance Company -
Convertible................ $ 625,000 $ 625,000 23,434 23,434
Conseco Health Insurance
Company-Convertible........ $ 625,000 $ 625,000 23,434 23,434
Conseco Funds Group -
Convertible................ $ 1,000,000 $ 1,000,000 37,495 37,495
RS Midcap Opportunities
Fund....................... $ 1,000,000 $ 1,000,000 37,495 37,495
</TABLE>
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<TABLE>
<CAPTION>
Principal
Amount of
Notes Principal
Beneficially Amount of Common
Owned Prior Notes Stock Owned Common
to the Offered Prior to the Stock Offered
Name Offering Hereby Offering(1) Hereby(2)
---- ------------- ---------- ------------ -------------
<S> <C> <C> <C> <C>
BNP Arbitrage SNC.......... $ 3,000,000 $ 3,000,000 112,485 112,485
Highbridge International
LLC...................... $ 6,255,000 $ 6,255,000 234,533 234,533
AFTRA Health Fund........... $ 250,000 $ 250,000 9,373 9,373
Mainstay Convertible Fund... $ 3,000,000 $ 3,000,000 112,485 112,485
Coditec International Ltd.
E (VBL).................... $ 50,000 $ 50,000 1,874 1,874
Faria Fund Ltd.............. $ 50,000 $ 50,000 1,874 1,874
Federated Utility
Fund, Inc.................. $ 7,700,000 $ 7,700,000 288,713 288,713
Federated Insurance Series,
on behalf of its Federated
Utility Fund II............ $ 850,000 $ 850,000 31,871 31,871
SunAmerica Series Trust, on
behalf of its Federated
Utility Portfolio.......... $ 470,000 $ 470,000 17,622 17,622
California Public Employees
Retirement System.......... $ 2,000,000 $ 2,000,000 74,990 74,990
New York Life Insurance &
Annuity Corporation(6)..... $ 1,750,000 $ 1,750,000 65,616 65,616
New York Life Insurance
Company(6)................. $ 4,000,000 $ 4,000,000 149,981 149,981
First Mercury Insurance
Company--
Total Return............... $ 20,000 $ 20,000 749 749
Century National Insurance
Company.................... $ 300,000 $ 300,000 11,248 11,248
Nalco Chemical
Company.................... $ 250,000 $ 250,000 9,373 9,373
State of Oregon Equity...... $ 5,325,000 $ 5,325,000 199,662 199,662
Delaware PERS............... $ 1,400,000 $ 1,400,000 52,493 52,493
ICI American Holdings
Trust...................... $ 600,000 $ 600,000 22,497 22,497
Zeneca Holdings Trust....... $ 600,000 $ 600,000 22,497 22,497
Pacific Life Insurance
Company.................... $ 1,000,000 $ 1,000,000 37,495 37,495
Pitney Bowes Retirement
Fund....................... $ 2,000,000 $ 2,000,000 74,990 74,990
Sage Capital................ $ 1,300,000 $ 1,300,000 48,743 48,743
Subtotal(7)........ $ 95,729,000 $ 95,729,000 3,589,388 3,589,388
Any other holder of notes
or future transferee from
any such holder(4)(7)...... $ 4,271,000 $ 4,271,000 160,142(5) 160,142(5)
Total.............. $100,000,000 $100,000,000 3,749,531 3,749,531
</TABLE>
________________________
(1) Comprises the shares of common stock owned by each selling holder prior to
the offering, including the shares of common stock into which the notes held
by the selling holder are
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convertible at the initial conversion rate of $26.67 per share, excluding
fractional shares. Fractional shares will not be issued upon conversion of
the notes; rather, cash will be paid in lieu of fractional shares, if any.
The conversion price and the number of shares of common stock issuable upon
conversion of the notes are subject to adjustment under specified
circumstances, which are described in more detail under "Description of
Notes--Conversion of Notes." Accordingly, the number of shares of common
stock issuable upon conversion of the notes may increase or decrease from
time to time.
(2) Assumes conversion into common stock of the full amount of notes held by
the selling holder at the initial conversion rate of $26.67 per share and
the offering of those shares by the selling holder pursuant to this
prospectus. The conversion price and the number of shares of common stock
issuable upon conversion of the notes are subject to adjustment under
specified circumstances which are described in more detail under
"Description of Notes - Conversion of Notes." Accordingly, the number of
shares of common stock issuable upon conversion of the notes may increase or
decrease from time to time. Fractional shares will not be issued upon
conversion of the notes; rather, cash will be paid in lieu of fractional
shares, if any. The selling holders may offer and sell pursuant to the
prospectus, their notes, the shares of common stock into which the notes are
convertible, or both.
(3) Morgan Stanley & Co. Incorporated acted as a placement agent in connection
with the offer and sale of the notes in May 1999 and as lead underwriter in
the May 1999 public offering and sale of 5.25 million shares of
ITC/\DeltaCom's common stock. In addition, Morgan Stanley & Co. Incorporated
acted as a placement agent in connection with the offer and sale of our 11%
Senior Notes in November 1997, our 8 7/8% Senior Notes in March 1998 and our
9 3/4% Senior Notes in November 1998.
(4) Information concerning other selling holders of notes will be set forth in
prospectus supplements from time to time, as required. No holder may offer
notes pursuant to this prospectus until such holder is included as a selling
holder in a supplement to this prospectus in accordance with the
registration rights agreement.
(5) Assumes that any other holders of notes or any future transferee from any
such holder does not beneficially own any common stock other than common
stock into which the notes are convertible at the conversion price of
$26.67 per share.
(6) Information with respect to this selling holder is as of October 5, 1999.
(7) Reflects information as of September 30, 1999, except with respect to those
selling holders for which the information included in the table is as of
October 5, 1999. See footnote 6.
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