Costar Group, Inc.

CSGP·NASDAQ·$32.52Share Price as of 11/2·$13BMarket Cap as of 11/2

Financials

10-QQ3 ended 09/30/2610/28/26 10-QQ2 ended 06/30/2607/29/26 10-QQ1 ended 03/31/2604/29/26 10-KFY 202502/26/26 10-QQ3 ended 09/30/2510/29/25

Disclosures

8-KCurrent report10/27/26 8-KCurrent report08/21/26 8-KCurrent report07/28/26 8-KCurrent report07/13/26 8-KCurrent report06/25/26

Prospectuses and Registrations

S-8Registration of securities for employees07/29/26 S-8Registration of securities for employees07/23/25 S-8Registration of securities for employees02/28/25 424B3Prospectus06/10/24 S-4/ARegistration (business combination, amended)06/10/24

Proxies

DEFA14AAdditional proxy materials05/18/26 DEF 14ADefinitive proxy04/30/26 DEFA14AAdditional proxy materials04/30/26 DEFA14AAdditional proxy materials06/13/25 DEFA14AAdditional proxy materials05/01/25

Ownership

Form 4Insider transaction10/16/26 SC 13GBeneficial ownership08/14/26 Form 4Insider transaction08/10/26 Form 4Insider transaction08/10/26 144Proposed sale of securities08/05/26

Other

SDConflict Minerals disclosure05/20/26 ARSAnnual report to shareholders04/30/26 ARSAnnual report to shareholders04/30/25 EFFECTRequest for effectiveness06/10/24 CORRESPCorrespondence with the SEC06/07/24