<SEC-DOCUMENT>0001057352-15-000072-index.html : 20150914
<SEC-HEADER>0001057352-15-000072.hdr.sgml : 20150914
<ACCEPTANCE-DATETIME>20150914163508
ACCESSION NUMBER:		0001057352-15-000072
CONFORMED SUBMISSION TYPE:	S-8
PUBLIC DOCUMENT COUNT:		5
FILED AS OF DATE:		20150914
DATE AS OF CHANGE:		20150914
EFFECTIVENESS DATE:		20150914

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:		S-8
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-206929
		FILM NUMBER:		151105818

	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>S-8
<SEQUENCE>1
<FILENAME>forms-8forplanamendmentand.htm
<DESCRIPTION>S-8
<TEXT>
Document 1 - file: forms-8forplanamendmentand.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-4.4
<SEQUENCE>2
<FILENAME>espp-amendedandrestatedtoi.htm
<DESCRIPTION>EXHIBIT 4.4
<TEXT>
Document 2 - file: espp-amendedandrestatedtoi.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-5.1
<SEQUENCE>3
<FILENAME>gdcs-8esppopinion.htm
<DESCRIPTION>EXHIBIT 5.1
<TEXT>
Document 3 - file: gdcs-8esppopinion.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-23.1
<SEQUENCE>4
<FILENAME>eyconsent.htm
<DESCRIPTION>EXHIBIT 23.1
<TEXT>
Document 4 - file: eyconsent.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>5
<FILENAME>gdcs8esppopinionimage1.gif
<TEXT>
Document 5 - file: gdcs8esppopinionimage1.gif

</DOCUMENT>
</SEC-DOCUMENT>