COSTAR GROUP, INC. — Director's Dealing 2010

Jun 21, 2010

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: COSTAR GROUP INC (CSGP)
CIK: 0001057352
Period of Report: 2010-06-20

Reporting Person: Stanfill John L (Sr. VP-Sales, Customer Service)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2010-06-20	Common Stock, par value $0.01 per share	A	37	—	Acquired	52173	Direct

Footnotes

F1: Service award granted by the Company for the reporting person's fifteen-year anniversary of employment. On the trading day immediately preceding the date of grant, the closing stock price of the Company's common stock was $41.00.

F2: Represents all shares of Common Stock owned, consisting of 5,931 shares of Common Stock and 46,242 shares of Common Stock subject to unvested Restricted Stock Grants.