COSTAR GROUP, INC. — Director's Dealing 2013

Aug 1, 2013

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: COSTAR GROUP INC (CSGP)
CIK: 0001057352
Period of Report: 2013-07-30

Reporting Person: CARCHEDI FRANCIS (Executive VP, Operations)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2013-07-30	Common Stock, par value $0.01 per share	M	10325	$37.42	Acquired	42551	Direct
2013-07-30	Common Stock, par value $0.01 per share	S	10325	$157.00	Disposed	32226	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2013-07-30	Option to Acquire Common Stock	$37.42	M	10325	Disposed	2019-07-15	Common Stock (10325)	Direct

Footnotes

F1: Represents all shares of Common Stock owned, consisting of 12,967 shares of Common Stock and 29,584 shares of Common Stock subject to unvested Restricted Stock Grants.

F2: Represents all shares of Common Stock owned, consisting of 2,642 shares of Common Stock and 29,584 shares of Common Stock subject to unvested Restricted Stock Grants.

F3: The option vested in four equal installments on July 16, 2010, July 16, 2011, July 16, 2012 and July 16, 2013.