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NASDAQ: CHKOTCPK: CHKAQ
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FormDescriptionDateFormat
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.
NO ACTNo Action LettersMar 27, 2012Open No Action Letters in HTML.Open No Action Letters in DOC file.Open No Action Letters in PDF file.Open No Action Letters in XLS file.
8-KReport of unscheduled material events or corporate eventMar 19, 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.
4Statement of changes in beneficial ownership of securitiesMar 16, 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.
8-KReport of unscheduled material events or corporate eventMar 9, 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.
CERTNYSCertification by the New York Stock Exchange approving securities for listingMar 6, 2012Open Certification by the New York Stock Exchange approving securities for listing in HTML.Open Certification by the New York Stock Exchange approving securities for listing in DOC file.Open Certification by the New York Stock Exchange approving securities for listing in PDF file.Open Certification by the New York Stock Exchange approving securities for listing in XLS file.
4Statement of changes in beneficial ownership of securitiesMar 5, 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 securitiesMar 5, 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 securitiesMar 5, 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 securitiesMar 5, 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 securitiesMar 5, 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 securitiesMar 5, 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 securitiesMar 5, 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 securitiesMar 5, 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.
10-KAnnual report which provides a comprehensive overview of the company for the past yearFeb 29, 2012Open Annual report which provides a comprehensive overview of the company for the past year in HTML.Open Annual report which provides a comprehensive overview of the company for the past year in DOC file.Open Annual report which provides a comprehensive overview of the company for the past year in PDF file.Open Annual report which provides a comprehensive overview of the company for the past year in XLS file.Open Annual report which provides a comprehensive overview of the company for the past year in XBLR Viewer.Open Annual report which provides a comprehensive overview of the company for the past year in XBLR file.
8-A12BRegistration of certain classes of securities 12(b) of the Securities Exchange ActFeb 24, 2012Open Registration of certain classes of securities 12(b) of the Securities Exchange Act in HTML.Open Registration of certain classes of securities 12(b) of the Securities Exchange Act in DOC file.Open Registration of certain classes of securities 12(b) of the Securities Exchange Act in PDF file.Open Registration of certain classes of securities 12(b) of the Securities Exchange Act in XLS file.
8-KReport of unscheduled material events or corporate eventFeb 21, 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 eventFeb 17, 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.
SC 13GSchedule filed to report acquisition of beneficial ownership of 5% or more of a class of equity securities by passive investors and certain institutionsFeb 14, 2012Open Schedule filed to report acquisition of beneficial ownership of 5% or more of a class of equity securities by passive investors and certain institutions in HTML.Open Schedule filed to report acquisition of beneficial ownership of 5% or more of a class of equity securities by passive investors and certain institutions in DOC file.Open Schedule filed to report acquisition of beneficial ownership of 5% or more of a class of equity securities by passive investors and certain institutions in PDF file.Open Schedule filed to report acquisition of beneficial ownership of 5% or more of a class of equity securities by passive investors and certain institutions in XLS file.
424B2Form of prospectus filed in connection with primary offering of securities on a delayed basisFeb 14, 2012Open Form of prospectus filed in connection with primary offering of securities on a delayed basis in HTML.Open Form of prospectus filed in connection with primary offering of securities on a delayed basis in DOC file.Open Form of prospectus filed in connection with primary offering of securities on a delayed basis in PDF file.Open Form of prospectus filed in connection with primary offering of securities on a delayed basis in XLS file.
SC 13G/AAmendment to a previously filed SC 13GFeb 14, 2012Open Amendment to a previously filed SC 13G in HTML.Open Amendment to a previously filed SC 13G in DOC file.Open Amendment to a previously filed SC 13G in PDF file.Open Amendment to a previously filed SC 13G in XLS file.
FWPFree Writing ProspectusFeb 13, 2012Open Free Writing Prospectus in HTML.Open Free Writing Prospectus in DOC file.Open Free Writing Prospectus in PDF file.Open Free Writing Prospectus in XLS file.
424B5Form of prospectus disclosing information facts events covered in both forms 424B2 424B3Feb 13, 2012Open Form of prospectus disclosing information facts events covered in both forms 424B2 424B3 in HTML.Open Form of prospectus disclosing information facts events covered in both forms 424B2 424B3 in DOC file.Open Form of prospectus disclosing information facts events covered in both forms 424B2 424B3 in PDF file.Open Form of prospectus disclosing information facts events covered in both forms 424B2 424B3 in XLS file.
POSASRPost-effective Amendment to an automatic shelf registration statement on Form S-3ASR or Form F-3ASRFeb 13, 2012Open Post-effective Amendment to an automatic shelf registration statement on Form S-3ASR or Form F-3ASR in HTML.Open Post-effective Amendment to an automatic shelf registration statement on Form S-3ASR or Form F-3ASR in DOC file.Open Post-effective Amendment to an automatic shelf registration statement on Form S-3ASR or Form F-3ASR in PDF file.Open Post-effective Amendment to an automatic shelf registration statement on Form S-3ASR or Form F-3ASR in XLS file.
FWPFree Writing ProspectusFeb 13, 2012Open Free Writing Prospectus in HTML.Open Free Writing Prospectus in DOC file.Open Free Writing Prospectus in PDF file.Open Free Writing Prospectus in XLS file.
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