<SEC-DOCUMENT>0001193125-14-222589-index.html : 20140623
<SEC-HEADER>0001193125-14-222589.hdr.sgml : 20140623
<ACCEPTANCE-DATETIME>20140602172638
ACCESSION NUMBER:		0001193125-14-222589
CONFORMED SUBMISSION TYPE:	424B2
PUBLIC DOCUMENT COUNT:		4
FILED AS OF DATE:		20140602
DATE AS OF CHANGE:		20140602

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			COSTAR GROUP INC
		CENTRAL INDEX KEY:			0001057352
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-BUSINESS SERVICES, NEC [7389]
		IRS NUMBER:				522091509
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		424B2
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-196466
		FILM NUMBER:		14885194

	BUSINESS ADDRESS:	
		STREET 1:		1331 L STREET NW
		CITY:			WASHINGTON
		STATE:			DC
		ZIP:			20005
		BUSINESS PHONE:		2023466500

	MAIL ADDRESS:	
		STREET 1:		1331 L STREET NW
		CITY:			WASHINGTON
		STATE:			DC
		ZIP:			20005
</SEC-HEADER>
<DOCUMENT>
<TYPE>424B2
<SEQUENCE>1
<FILENAME>d734477d424b2.htm
<DESCRIPTION>424B2
<TEXT>
Document 1 - file: d734477d424b2.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>2
<FILENAME>g734477g27b94.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 2 - file: g734477g27b94.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>3
<FILENAME>g734477g56j44.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 3 - file: g734477g56j44.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>4
<FILENAME>g735388g40z46.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 4 - file: g735388g40z46.jpg

</DOCUMENT>
</SEC-DOCUMENT>