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NASDAQ: CHKOTCPK: CHKAQ
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FormDescriptionDateFormat
4Statement of changes in beneficial ownership of securitiesJun 29, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesJun 27, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesJun 20, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesJun 18, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesJun 11, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesMay 25, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesMay 25, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesMay 14, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesMay 14, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesMay 14, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesMay 4, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4/AAmendment to a previously filed 4Apr 19, 2007Open Amendment to a previously filed 4 in HTML.Open Amendment to a previously filed 4 in DOC file.Open Amendment to a previously filed 4 in PDF file.Open Amendment to a previously filed 4 in XLS file.
4Statement of changes in beneficial ownership of securitiesApr 3, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesApr 3, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesApr 3, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesApr 3, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesApr 3, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesApr 3, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesApr 3, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesApr 3, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesApr 3, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesApr 2, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesMar 28, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesMar 28, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
4Statement of changes in beneficial ownership of securitiesMar 26, 2007Open Statement of changes in beneficial ownership of securities in HTML.Open Statement of changes in beneficial ownership of securities in DOC file.Open Statement of changes in beneficial ownership of securities in PDF file.Open Statement of changes in beneficial ownership of securities in XLS file.
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