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NASDAQ: CHKOTCPK: CHKAQ
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FormDescriptionDateFormat
4Statement of changes in beneficial ownership of securitiesJun 15, 2006Open 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.
8-KReport of unscheduled material events or corporate eventJun 15, 2006Open Report of unscheduled material events or corporate event in HTML.Open Report of unscheduled material events or corporate event in DOC file.Open Report of unscheduled material events or corporate event in PDF file.Open Report of unscheduled material events or corporate event in XLS file.
8-KReport of unscheduled material events or corporate eventJun 15, 2006Open Report of unscheduled material events or corporate event in HTML.Open Report of unscheduled material events or corporate event in DOC file.Open Report of unscheduled material events or corporate event in PDF file.Open Report of unscheduled material events or corporate event in XLS file.
8-KReport of unscheduled material events or corporate eventJun 15, 2006Open Report of unscheduled material events or corporate event in HTML.Open Report of unscheduled material events or corporate event in DOC file.Open Report of unscheduled material events or corporate event in PDF file.Open Report of unscheduled material events or corporate event in XLS file.
4Statement of changes in beneficial ownership of securitiesJun 14, 2006Open 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 14, 2006Open 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 13, 2006Open 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 13, 2006Open 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 13, 2006Open 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 12, 2006Open 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 12, 2006Open 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 12, 2006Open 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 9, 2006Open 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.
8-KReport of unscheduled material events or corporate eventJun 8, 2006Open Report of unscheduled material events or corporate event in HTML.Open Report of unscheduled material events or corporate event in DOC file.Open Report of unscheduled material events or corporate event in PDF file.Open Report of unscheduled material events or corporate event in XLS file.
8-KReport of unscheduled material events or corporate eventJun 8, 2006Open Report of unscheduled material events or corporate event in HTML.Open Report of unscheduled material events or corporate event in DOC file.Open Report of unscheduled material events or corporate event in PDF file.Open Report of unscheduled material events or corporate event in XLS file.
8-KReport of unscheduled material events or corporate eventJun 6, 2006Open Report of unscheduled material events or corporate event in HTML.Open Report of unscheduled material events or corporate event in DOC file.Open Report of unscheduled material events or corporate event in PDF file.Open Report of unscheduled material events or corporate event in XLS file.
4Statement of changes in beneficial ownership of securitiesJun 6, 2006Open 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.
424B3Form of prospectus reflecting facts events constituting substantive change from last formJun 5, 2006Open Form of prospectus reflecting facts events constituting substantive change from last form in HTML.Open Form of prospectus reflecting facts events constituting substantive change from last form in DOC file.Open Form of prospectus reflecting facts events constituting substantive change from last form in PDF file.Open Form of prospectus reflecting facts events constituting substantive change from last form in XLS file.
SC TO-I/AAmendment to a previously filed SC TO-IJun 2, 2006Open Amendment to a previously filed SC TO-I in HTML.Open Amendment to a previously filed SC TO-I in DOC file.Open Amendment to a previously filed SC TO-I in PDF file.Open Amendment to a previously filed SC TO-I in XLS file.
SC TO-I/AAmendment to a previously filed SC TO-IJun 2, 2006Open Amendment to a previously filed SC TO-I in HTML.Open Amendment to a previously filed SC TO-I in DOC file.Open Amendment to a previously filed SC TO-I in PDF file.Open Amendment to a previously filed SC TO-I in XLS file.
SC TO-I/AAmendment to a previously filed SC TO-IMay 31, 2006Open Amendment to a previously filed SC TO-I in HTML.Open Amendment to a previously filed SC TO-I in DOC file.Open Amendment to a previously filed SC TO-I in PDF file.Open Amendment to a previously filed SC TO-I in XLS file.
8-KReport of unscheduled material events or corporate eventMay 31, 2006Open Report of unscheduled material events or corporate event in HTML.Open Report of unscheduled material events or corporate event in DOC file.Open Report of unscheduled material events or corporate event in PDF file.Open Report of unscheduled material events or corporate event in XLS file.
SC TO-I/AAmendment to a previously filed SC TO-IMay 31, 2006Open Amendment to a previously filed SC TO-I in HTML.Open Amendment to a previously filed SC TO-I in DOC file.Open Amendment to a previously filed SC TO-I in PDF file.Open Amendment to a previously filed SC TO-I in XLS file.
SC TO-I/AAmendment to a previously filed SC TO-IMay 25, 2006Open Amendment to a previously filed SC TO-I in HTML.Open Amendment to a previously filed SC TO-I in DOC file.Open Amendment to a previously filed SC TO-I in PDF file.Open Amendment to a previously filed SC TO-I in XLS file.
SC TO-I/AAmendment to a previously filed SC TO-IMay 25, 2006Open Amendment to a previously filed SC TO-I in HTML.Open Amendment to a previously filed SC TO-I in DOC file.Open Amendment to a previously filed SC TO-I in PDF file.Open Amendment to a previously filed SC TO-I in XLS file.
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