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NASDAQ: CHKOTCPK: CHKAQ
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FormDescriptionDateFormat
8-KReport of unscheduled material events or corporate eventMay 3, 2012Open 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.
UPLOADCorrespondence from the SEC to the FilerMay 3, 2012Open Correspondence from the SEC to the Filer in HTML.Open Correspondence from the SEC to the Filer in DOC file.Open Correspondence from the SEC to the Filer in PDF file.Open Correspondence from the SEC to the Filer in XLS file.
SC 13DFiling by person(s) reporting owned shares of common stock in a public company >5%May 2, 2012Open Filing by person(s) reporting owned shares of common stock in a public company >5% in HTML.Open Filing by person(s) reporting owned shares of common stock in a public company >5% in DOC file.Open Filing by person(s) reporting owned shares of common stock in a public company >5% in PDF file.Open Filing by person(s) reporting owned shares of common stock in a public company >5% in XLS file.
8-KReport of unscheduled material events or corporate eventMay 2, 2012Open 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.
DEFA14AAdditional proxy soliciting materials - definitiveMay 2, 2012Open Additional proxy soliciting materials - definitive in HTML.Open Additional proxy soliciting materials - definitive in DOC file.Open Additional proxy soliciting materials - definitive in PDF file.Open Additional proxy soliciting materials - definitive in XLS file.
4Statement of changes in beneficial ownership of securitiesMay 2, 2012Open 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 2, 2012Open 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.
DEFA14AAdditional proxy soliciting materials - definitiveMay 1, 2012Open Additional proxy soliciting materials - definitive in HTML.Open Additional proxy soliciting materials - definitive in DOC file.Open Additional proxy soliciting materials - definitive in PDF file.Open Additional proxy soliciting materials - definitive in XLS file.
8-KReport of unscheduled material events or corporate eventMay 1, 2012Open 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.
10-K/AAmendment to a previously filed 10-KApr 30, 2012Open Amendment to a previously filed 10-K in HTML.Open Amendment to a previously filed 10-K in DOC file.Open Amendment to a previously filed 10-K in PDF file.Open Amendment to a previously filed 10-K in XLS file.
UPLOADCorrespondence from the SEC to the FilerApr 30, 2012Open Correspondence from the SEC to the Filer in HTML.Open Correspondence from the SEC to the Filer in DOC file.Open Correspondence from the SEC to the Filer in PDF file.Open Correspondence from the SEC to the Filer in XLS file.
CORRESPCorrespondence from the Filer to the SECApr 30, 2012Open Correspondence from the Filer to the SEC in HTML.Open Correspondence from the Filer to the SEC in DOC file.Open Correspondence from the Filer to the SEC in PDF file.Open Correspondence from the Filer to the SEC in XLS file.
8-KReport of unscheduled material events or corporate eventApr 26, 2012Open 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.
DEFA14AAdditional proxy soliciting materials - definitiveApr 26, 2012Open Additional proxy soliciting materials - definitive in HTML.Open Additional proxy soliciting materials - definitive in DOC file.Open Additional proxy soliciting materials - definitive in PDF file.Open Additional proxy soliciting materials - definitive in XLS file.
DFAN14AAdditional proxy soliciting materials filed by non-managementApr 26, 2012Open Additional proxy soliciting materials filed by non-management in HTML.Open Additional proxy soliciting materials filed by non-management in DOC file.Open Additional proxy soliciting materials filed by non-management in PDF file.Open Additional proxy soliciting materials filed by non-management in XLS file.
PRE 14AA preliminary proxy statement providing notification matters to be brought to a voteApr 20, 2012Open A preliminary proxy statement providing notification matters to be brought to a vote in HTML.Open A preliminary proxy statement providing notification matters to be brought to a vote in DOC file.Open A preliminary proxy statement providing notification matters to be brought to a vote in PDF file.Open A preliminary proxy statement providing notification matters to be brought to a vote in XLS file.
8-KReport of unscheduled material events or corporate eventApr 20, 2012Open 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 eventApr 13, 2012Open 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 eventApr 5, 2012Open 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.
4/AAmendment to a previously filed 4Apr 3, 2012Open 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, 2012Open 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, 2012Open 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, 2012Open 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, 2012Open 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, 2012Open 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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