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Organization (Tables) | 6 Months Ended
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Jun. 30, 2011
Organization. |
Summary of forms of ownership and percentage of ownership forms |
A summary of our Operating Partnership’s forms of ownership and the percentage of those ownership forms owned by COPT as of June 30, 2011 follows:
Common Units |  | 94 | %
Series G Preferred Units |  | 100 | %
Series H Preferred Units |  | 100 | %
Series I Preferred Units |  | 0 | %
Series J Preferred Units |  | 100 | %
Series K Preferred Units |  | 100 | %

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- Definition Tabular disclosure of operating partnership's forms of ownership and the percentage of ownership forms owned by the parent company. + Details
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