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EXHIBIT 21.1

Name	Percent of Capital Stock/Equity Units Owned by Steel Dynamics, Inc.		Percent of Voting Stock/Voting Units Owned by Steel Dynamics, Inc.
Dynamic Aviation, LLC (Indiana)	100	%	100	%
New Millennium Building Systems, LLC (Indiana)	100	%	100	%
OmniSource Corporation (Indiana)	100	%	100	%
Paragon Steel Enterprises, LLC (Indiana)	50	%	50	%
Roanoke Electric Steel Corporation (Indiana)	100	%	100	%
SDI Investment Company (Delaware)	100	%	100	%
Shredded Products II, LLC (Virginia)	100	%	100	%
Steel Dynamics Sales North America, Inc. (Indiana)	100	%	100	%
STLD Holdings, Inc. (Indiana)	100	%	100	%
The Techs Industries, Inc. (Pennsylvania)	100	%	100	%

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EXHIBIT 21.1