<SEC-DOCUMENT>0001140361-20-011938-index.html : 20200519
<SEC-HEADER>0001140361-20-011938.hdr.sgml : 20200519
<ACCEPTANCE-DATETIME>20200519160300
ACCESSION NUMBER:		0001140361-20-011938
CONFORMED SUBMISSION TYPE:	S-3ASR
PUBLIC DOCUMENT COUNT:		7
FILED AS OF DATE:		20200519
DATE AS OF CHANGE:		20200519
EFFECTIVENESS DATE:		20200519

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-3ASR
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-238500
		FILM NUMBER:		20893592

	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

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	COSTAR GROUP INC
		DATE OF NAME CHANGE:	19990805
</SEC-HEADER>
<DOCUMENT>
<TYPE>S-3ASR
<SEQUENCE>1
<FILENAME>nt10012107x1_s3asr.htm
<DESCRIPTION>S-3ASR
<TEXT>
Document 1 - file: nt10012107x1_s3asr.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-5.1
<SEQUENCE>2
<FILENAME>nt10012107x1_ex5-1.htm
<DESCRIPTION>EXHIBIT 5.1
<TEXT>
Document 2 - file: nt10012107x1_ex5-1.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-23.1
<SEQUENCE>3
<FILENAME>nt10012107x1_ex23-1.htm
<DESCRIPTION>EXHIBIT 23.1
<TEXT>
Document 3 - file: nt10012107x1_ex23-1.htm

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

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>5
<FILENAME>nt10012107x1_ex5-1gdfooter.jpg
<TEXT>
Document 5 - file: nt10012107x1_ex5-1gdfooter.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>6
<FILENAME>nt10012107x1_ex5-1gdheader01.jpg
<TEXT>
Document 6 - file: nt10012107x1_ex5-1gdheader01.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>7
<FILENAME>nt10012107x1_ex5-1gdheader02.jpg
<TEXT>
Document 7 - file: nt10012107x1_ex5-1gdheader02.jpg

</DOCUMENT>
</SEC-DOCUMENT>