SEC Filings

Form	Description	Filing date	View
DEFA14A	Additional proxy soliciting materials - definitive	Apr 07, 2021	View HTML 0001097149-21-000020.pdf
DEFA14A	Additional proxy soliciting materials - definitive	Apr 05, 2022	View HTML 0001097149-22-000016.pdf
DEFA14A	Additional proxy soliciting materials - definitive	Apr 05, 2023	View HTML 0001097149-23-000030.pdf
DEFA14A	Additional proxy soliciting materials - definitive	May 01, 2023	View HTML 0001097149-23-000041.pdf
DEFA14A	Additional proxy soliciting materials - definitive	Apr 09, 2024	View HTML 0001097149-24-000019.pdf
DEFR14A	DEFR14A	Apr 16, 2024	View HTML 0001097149-24-000023.pdf 0001097149-24-000023.xls EX-101.SCH - XBRL TAXONOMY EXTENSION SCHEMA
POS AM	Post-effective amendment to an S-Type filing	Apr 19, 2005	View HTML 0001047469-05-010689.pdf 0001047469-05-010689.xls
PRE 14A	A preliminary proxy statement providing notification matters to be brought to a vote	Mar 17, 2016	View HTML 0001097149-16-000037.pdf 0001097149-16-000037.xls
PRE 14A	A preliminary proxy statement providing notification matters to be brought to a vote	Mar 26, 2021	View HTML 0001097149-21-000012.pdf 0001097149-21-000012.xls
PRE 14A	A preliminary proxy statement providing notification matters to be brought to a vote	Mar 23, 2023	View HTML 0001097149-23-000020.pdf 0001097149-23-000020.xls EX-101.SCH - XBRL TAXONOMY EXTENSION SCHEMA