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Exhibit 99.1


UNAUDITED PRO FORMA CONDENSED CONSOLIDATED FINANCIAL INFORMATION

        On October 1, 2007, Steel Dynamics entered into a definitive purchase agreement to acquire the net assets (excluding the assumption of approximately $210 million in debt as discussed below) of OmniSource and its subsidiaries (the "Acquisition") for total consideration of approximately $1.1 billion consisting of 9.7 million shares of Steel Dynamics common stock, $441 million in cash, including estimated transaction fees, along with the assumption of debt at closing of approximately $210 million. We will finance the cash portion of the Acquisition, and refinance the assumed liabilities, with $661.5 million of borrowings consisting of $500 million aggregate principal amount of notes and $161.5 million under our senior secured revolving credit facility (these borrowings, together with the Acquisition, are referred to as the "Transactions"). This assumed OmniSource debt is expected to be extinguished by Steel Dynamics soon after the closing of the Acquisition. While Steel Dynamics acquired the stock of OmniSource, for tax purposes, the transaction will be treated as an asset purchase. In addition to the Acquisition, we have agreed to purchase certain real estate assets from some of the shareholders of OmniSource for $10 million following the closing of the Acquisition. This real estate purchase is not reflected in the pro forma financial information.

        The following unaudited pro forma condensed consolidated financial information is derived from and should be read in conjunction with historical financial statements and related notes of Steel Dynamics and OmniSource which are incorporated by reference for Steel Dynamics and included elsewhere in this offering memorandum for OmniSource.

        The unaudited pro forma condensed consolidated balance sheet as of June 30, 2007 and the unaudited pro forma condensed statements of income for the twelve months ended December 31, 2006 and the six months ended June 30, 2007 are presented herein. The unaudited pro forma condensed consolidated balance sheet gives effect to the Transactions as if they occurred on June 30, 2007 and combines the historical balance sheets of Steel Dynamics and OmniSource as of June 30, 2007. The unaudited pro forma condensed consolidated statements of income for the twelve months ended December 31, 2006 give effect to the Transactions as if they occurred on January 1, 2006 and combine the historical consolidated statements of income from Steel Dynamics for the twelve months ended December 31, 2006 with the historical statements of income of OmniSource for the twelve months ended September 30, 2006. The unaudited pro forma condensed consolidated statements of income for the six months ended June 30, 2007 give effect to the Transactions as if they occurred on January 1, 2007 and combine the historical consolidated statements of income of Steel Dynamics and OmniSource for the six months ended June 30, 2007. The historical consolidated income statements of OmniSource for the three months ended December 31, 2006 have not been used in preparation of these pro forma income statements. Net sales and income before taxes for OmniSource were $485 million and $9 million, respectively, for this three month period.

        The historical financial statements have been adjusted to give effect to pro forma items that are (i) directly attributable to the Transactions and (ii) factually supportable. The unaudited pro forma condensed consolidated financial information is presented for illustrative purposes only and is not necessarily indicative of what the actual combined financial position or results of operations would have been had the Transactions been completed on the dates indicated or what such financial position or results would be for future periods.

        The unaudited pro forma condensed consolidated financial statements were prepared using the purchase method of accounting to account for the Acquisition. Accordingly, we have adjusted the historical consolidated financial information to give effect to the consideration issued in connection with the Acquisition. In the unaudited pro forma condensed consolidated financial statements, Steel Dynamics' costs to acquire OmniSource have been allocated to the assets acquired and the liabilities assumed based upon management's preliminary estimate of their respective fair values. Any excess of the fair value of the consideration issued over the fair value of the identifiable assets acquired and liabilities assumed will be recorded as goodwill. The amounts allocated to the identifiable assets



acquired and liabilities assumed in the unaudited pro forma condensed consolidated financial information are based upon management's preliminary valuation estimates. Definitive allocations will be finalized based on certain valuations and other studies that will be performed by Steel Dynamics, in some cases with the assistance of outside valuation specialists, after the closing of the Acquisition. Accordingly, the purchase price allocation adjustments and related depreciation and amortization reflected in the unaudited pro forma condensed consolidated financial statements are preliminary, have been made solely for the purpose of preparing these statements and are subject to revision based on a final determination of fair value after closing of the Acquisition, and such revisions could have a material effect on the accompanying unaudited pro forma condensed consolidated financial statements.

        The unaudited pro forma condensed consolidated statements of income do not include the impacts of any revenue, costs or other operating synergies that may result from the Acquisition or any related restructuring costs. The unaudited pro forma condensed consolidated statements of income also do not reflect certain costs to be incurred resulting from the Acquisition because we consider them to be of a non-recurring nature.

        Based on Steel Dynamics' review of OmniSource's significant accounting policies disclosed in the latter's historical financials statements, the nature and amount of any adjustments to the historical financial statements of OmniSource to conform their accounting policies to those of Steel Dynamics' are not expected to be significant. Upon consummation of the Acquisition, further review of OmniSource's accounting policies and financial statements may result in required revisions to OmniSource's policies and classifications to conform to Steel Dynamics' accounting policies.

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Unaudited Pro Forma Condensed Consolidated Balance Sheet
As of June 30, 2007
(Dollars in thousands, except per share data)

 
  Historical
   
   
 
 
  Steel
Dynamics

  OmniSource
  Transactions
  Pro Forma
 
Assets                          
  Cash and equivalents   $ 12,212   $ 10,597   $ (12,809 )(e)(f)(g) $ 10,000  
  Accounts receivable, less allowance for doubtful accounts     442,124     346,424     (14,671) (o)   773,877  
  Inventories     726,236     141,556         867,792  
  Deferred income taxes     14,488             14,488  
  Other current assets     31,493     26,265         57,758  
   
 
 
 
 
    Total current assets     1,226,553     524,842     (27,480 )   1,723,915  
  Property, plant and equipment, net     1,249,178     165,998     30,000   (a)   1,445,176  
  Investments         42,271         42,271  
  Restricted cash     6,592             6,592  
  Intangible assets, net     14,110         180,000   (b)   194,110  
  Goodwill     48,490     79,931     377,219   (c)   505,640  
  Other assets     30,963     6,774     4,000   (g)   41,737  
   
 
 
 
 
    Total assets   $ 2,575,886   $ 819,816   $ 563,739   $ 3,959,441  
   
 
 
 
 
Liabilities and Stockholders' Equity                          
  Accounts payable   $ 218,318   $ 256,199   $ (40,025) (f)(o) $ 434,492  
  Income taxes payable     26,365             26,365  
  Accrued expenses     92,401     42,484         134,885  
  Accrued profit sharing     27,619             27,619  
  Senior secured revolving credit facility     215,000     19,734     141,742   (f)   376,476  
  Current maturities of long-term debt     699             699  
   
 
 
 
 
    Total current liabilities     580,402     318,417     101,717     1,000,536  
  Senior 63/4% notes, due 2015     500,000             500,000  
  New notes, due 2012             500,000   (g)   500,000  
  Convertible subordinated 4.0% notes, due 2012     37,500             37,500  
  Other secured debt     16,750     184,197     (184,197) (f)   16,750  
   
 
 
 
 
    Total long term debt     554,250     184,197     315,803     1,054,250  
  Deferred income taxes     256,210             256,210  
  Other long term liability         3,544         3,544  
  Minority interest     869             869  
  Commitments and contingencies                          
Stockholders' Equity                          
  Common stock, at $.005 par value     540     3,969     (3,969) (d)   540  
  Treasury stock     (464,405 )       300,700   (e)   (163,705 )
  Additional paid-in capital     386,935         159,177   (e)   546,112  
  Retained earnings     1,261,085     309,689     (309,689) (d)   1,261,085  
   
 
 
 
 
    Total stockholders' equity     1,184,155     313,658     146,219     1,644,032  
   
 
 
 
 
    Total liabilities and stockholders' equity   $ 2,575,886   $ 819,816   $ 563,739   $ 3,959,441  
   
 
 
 
 

See Notes to Unaudited Pro Forma Condensed Consolidated Financial Information

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Unaudited Pro Forma Condensed Consolidated Statements of Income
For the Year Ended December 31, 2006
(Dollars in thousands, except per share data)

 
  Historical
   
   
 
 
  Fiscal Year Ended
December 31, 2006

  Fiscal Year Ended
September 30, 2006

   
   
 
 
  Steel Dynamics
  OmniSource
  Transactions
  Pro Forma
 
Net sales   $ 3,238,787   $ 2,254,765   $ (126,980) (k) $ 5,366,572  
Costs of goods sold     2,408,795     2,062,058     (122,840) (i)(k)   4,348,013  
   
 
 
 
 
  Gross profit     829,992     192,707     (4,140 )   1,018,559  

Selling, general and administrative expenses

 

 

170,878

 

 

80,725

(x)

 

8,300

  (h)(m)

 

259,903

 
   
 
 
 
 
  Operating income     659,114     111,982     (12,440 )   758,656  

Interest expense

 

 

32,104

 

 

11,114

 

 

37,205

  (j)

 

80,423

 
Other expense (income), net     (4,545 )   (15,395 )       (19,940 )
   
 
 
 
 
  Income before income taxes     631,555     116,263     (49,645 )   698,173  
Income taxes     234,848     7,010     19,637   (n)   261,495  
   
 
 
 
 
  Net income   $ 396,707   $ 109,253   $ (69,282 ) $ 436,678  
   
 
 
 
 

Basic earnings per share

 

$

4.22

 

 

 

 

 

 

 

$

4.21

 
Weighted average common shares outstanding     93,931           9,700   (l)   103,631  
Diluted earnings per share   $ 3.77               $ 3.80  
Weighted average common shares and share equivalents outstanding     105,774           9,700   (l)   115,474  

(x)
This amount includes $11.3 million of gain on the sale of OmniSource's East Chicago scrapyard.

See Notes to Unaudited Pro Forma Condensed Consolidated Financial Information

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Unaudited Pro Forma Condensed Consolidated Statements of Income
For the Six Months Ended June 30, 2007
(Dollars in thousands, except per share data)

 
  Historical
   
   
 
  Steel Dynamics
  OmniSource
  Transactions
  Pro Forma
Net sales   $ 1,776,922   $ 1,308,369   $ (138,417) (k) $ 2,946,874
Costs of goods sold     1,343,937     1,196,235     (136,847) (i)(k)   2,404,575
   
 
 
 
  Gross profit     432,985     112,134     (2,820 )   542,299

Selling, general and administrative expenses

 

 

94,015

 

 

46,184

 

 

4,150

  (h)(m)

 

144,349
   
 
 
 
  Operating income     338,970     65,950     (6,970 )   397,950

Interest expense

 

 

14,444

 

 

7,480

 

 

16,679

  (j)

 

38,603
Other expense (income), net     10,807     (8,842 )       1,965
   
 
 
 
  Income before income taxes     313,719     67,312     (23,649 )   357,382
Income taxes     117,613     1,011     16,454   (n)   135,078
   
 
 
 
 
Net income

 

$

196,106

 

$

66,301

 

$

(40,103

)

$

222,304
   
 
 
 

Basic earnings per share

 

$

2.07

 

 

 

 

 

 

 

$

2.13
Weighted average common shares outstanding     94,873           9,700   (l)   104,573
Diluted earnings per share   $ 1.96               $ 2.03
Weighted average common shares and share equivalents outstanding     100,209           9,700   (l)   109,909

See Notes to Unaudited Pro Forma Condensed Consolidated Financial Information.

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NOTES TO THE UNAUDITED PRO FORMA CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(Dollars in thousands)

1.
Sources and Uses of Funds

        Set forth below are the estimated sources and uses of funds reflected in the Transactions column.

 
  Sources
   
  Uses
Senior secured revolving credit facility   $ 161,476   Cash and common stock to OmniSource   $ 890,877
Notes offered hereby     500,000   Acquisition fees and expenses     10,000
Cash on hand     12,809   Financing fees and expenses     4,000
Common stock     459,877   Repayment of OmniSource's existing indebtedness     229,285
   
     
    $ 1,134,162       $ 1,134,162
   
     

        For purposes of the pro forma financial statements the value of common stock to be issued to OmniSource is based upon the closing price of our common stock on October 1, 2007, the date the Acquisition was announced, of $47.41. Upon closing Steel Dynamics will issue 9.7 million shares of its common stock to OmniSource. The value assigned to the shares issued in the final purchase allocation will be based upon the average price of Steel Dynamics' common stock as listed on NASDAQ a few days before and after October 1, 2007, the date the Acquisition was announced.

2.
Purchase Price

        The estimated purchase price, excluding the assumption of OmniSource's existing indebtedness, and allocation of the estimated purchase price discussed below are preliminary as the proposed Acquisition has not yet been completed. The following is a preliminary estimate of the purchase price for the Acquisition.

Cash and common stock to OmniSource   $ 890,877
Estimated fees and expenses     10,000
   
Total estimated preliminary purchase price   $ 900,877
   

        Under the purchase method of accounting, the total estimated purchase price as shown in the table above is allocated to identifiable net tangible and intangible assets of OmniSource based on their estimated fair values as of the date of the Acquisition. The purchase price in excess of the identifiable assets acquired is allocated to Goodwill. The management of Steel Dynamics has allocated the preliminary estimated purchase price based on preliminary estimates. The allocation of the preliminary purchase price and the estimated useful lives associated with certain assets are as follows:

 
  Amount
  Estimated
Useful Life

Net tangible assets at book value   $ 233,727    
Property, plant and equipment step-up     30,000   12 years
Intangible assets          
  Customer relationships     150,000   20 years
  Trade names     30,000   Indefinite
Goodwill     457,150    
   
   
      Estimated preliminary purchase price   $ 900,877    
   
   

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        Definitive allocations will be finalized based on certain valuations and other studies that will be performed by Steel Dynamics, in some cases with the assistance of outside valuation specialists, after closing the Acquisition. Accordingly, the purchase price allocation adjustments and related depreciation and amortization reflected in the foregoing unaudited pro forma condensed consolidated financial statements are preliminary, have been made solely for the purpose of preparing these statements and are subject to revision based on a final determination of fair value after closing of the Acquisition, and such revisions could have a material effect on the accompanying unaudited pro forma condensed consolidated financial statements. Such revisions could include changes to the fair value assigned to tangible or intangible assets acquired or liabilities assumed, or changes to the estimated useful lives assigned to tangible or intangible assets.

        Identifiable intangible assets:    Customer relationships related primarily to underlying customer relationships with distributor networks, original equipment manufacturers and other customers of OmniSource. Acquired trade names include OmniSource.

        Steel Dynamics expects to amortize the fair value of customer relationships based on the pattern in which the economic benefits of this intangible asset will be consumed. Additionally, the customer relationships will be tested for impairment whenever circumstances indicate that the carrying amount may not be recoverable. The fair value of acquired trade names will not be amortized but instead will be tested for impairment at least annually (more frequently if indicators of impairment are present). In the event that management determines that the value of the acquired customer relationships or trade names has become impaired, Steel Dynamics will incur an accounting charge for the amount of impairment during the period in which the amount is determined.

        Goodwill:    Approximately $457,150 has been allocated to goodwill. Goodwill represents the excess of the purchase price over the fair value of the underlying identifiable net tangible and intangible assets. In accordance with Statement of Financial Accounting Standards ("SFAS") 142, Goodwill and Other Intangible Assets, goodwill will not be amortized but instead will be tested for impairment at least annually (more frequently if indicators of impairment are present). In the event that management determines that the value of the goodwill has become impaired, Steel Dynamics will incur an accounting charge for the amount of impairment during the period in which the amount is determined.

        Fixed assets:    Management has estimated that at acquisition date the fair values of certain fixed assets of OmniSource will be higher than their respective book values in their historical financial statements.

3.
Pro Forma Adjustments

        Pro Forma adjustments for the Transactions give effect to the Acquisition under the purchase method of accounting, the issuance of common stock to OmniSource, the issuance of the notes offered hereby, borrowings under the senior secured revolving credit facility, the repayment of OmniSource's existing indebtedness, and the payment of fees and expenses.

        The pro forma adjustments included in the unaudited pro forma condensed consolidated balance sheet are as described below:

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UNAUDITED PRO FORMA CONDENSED CONSOLIDATED FINANCIAL INFORMATION
Unaudited Pro Forma Condensed Consolidated Balance Sheet As of June 30, 2007 (Dollars in thousands, except per share data)
Unaudited Pro Forma Condensed Consolidated Statements of Income For the Year Ended December 31, 2006 (Dollars in thousands, except per share data)
Unaudited Pro Forma Condensed Consolidated Statements of Income For the Six Months Ended June 30, 2007 (Dollars in thousands, except per share data)
NOTES TO THE UNAUDITED PRO FORMA CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands)