COSTAR GROUP, INC. — Director's Dealing 2013

Mar 6, 2013

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: COSTAR GROUP INC (CSGP)
CIK: 0001057352
Period of Report: 2013-03-04

Reporting Person: FLORANCE ANDREW C (Director, President and CEO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2013-03-04	Common Stock, par value $0.01 per share	S	32330	$102.85	Disposed	268330	Direct
2013-03-04	Common Stock, par value $0.01 per share	F	2986	$103.17	Disposed	265344	Direct

Footnotes

F1: Average based on sales prices ranging from $102.18 to $103.48.

F2: Represents all shares of Common Stock owned, consisting of 87,562 shares of Common Stock and 180,768 shares of Common Stock subject to unvested Restricted Stock Grants.

F3: Represents all shares of Common Stock owned, consisting of 90,443 shares of Common Stock and 174,901 shares of Common Stock subject to unvested Restricted Stock Grants.