COSTAR GROUP, INC. — Director's Dealing 2014

Aug 27, 2014

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: COSTAR GROUP INC (CSGP)
CIK: 0001057352
Period of Report: 2014-08-26

Reporting Person: NASSETTA CHRISTOPHER J (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2014-08-26	Common Stock, par value $0.01 per share	M	5000	$44.86	Acquired	26346	Direct
2014-08-26	Common Sctock, par value $0.01 per share	S	3242	$148.11	Disposed	23104	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2014-08-26	Option to Acquire Common Stock	$44.86	M	5000	Disposed	2014-09-08	Common Stock (5000)	Direct

Footnotes

F1: Represents all shares of Common Stock owned, consisting of 23,020 shares of Common Stock and 3,326 shares of Common Stock subject to unvested Restricted Stock Grants.

F2: Average based on sales prices ranging from $148.00 to $148.21.

F3: Represents all shares of Common Stock owned, consisting of 19,778 shares of Common Stock and 3,326 shares of Common Stock subject to unvested Restricted Stock Grants.

F4: The option vested in four equal installments on September 9, 2005, September 9, 2006, September 9, 2007 and September 9, 2008.