UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 13F Form 13F COVER PAGE Report for the Calendar Year or Quarter Ended: December 31, 2006 Check here if Amendment [ ]; Amendment Number: -------- This Amendment (Check only one.): [ ] is a restatement. [ ] adds new holdings entries. Institutional Investment Manager Filing this Report: Name: Wesco Financial Corporation Address: 301 E. Colorado Blvd. Suite 300 Pasadena, CA 91101 Form 13F File Number: 28-1357 The institutional investment manager filing this report and the person by whom it is signed hereby represent that the person signing the report is authorized to submit it, that all information contained herein is true, correct and complete, and that it is understood that all required items, statements, schedules, lists, and tables, are considered integral parts of this form. Person Signing this Report on Behalf of Reporting Manager: Name: Jeffrey L. Jacobson Title: Vice President Phone: 626-585-6700 Signature, Place, and Date of Signing: /s/ Jeffrey L. Jacobson Pasadena, CA February 13, 2007 ------------------------------------- -------------------- ----------------- [Signature] [City, State] [Date] Report Type (Check only one.): [ ] 13F HOLDINGS REPORT. (Check here if all holdings of this reporting manager are reported in this report.) [X] 13F NOTICE. (Check here if no holdings reported are in this report, and all holdings are reported by other reporting manager(s).) [ ] 13F COMBINATION REPORT. (Check here if a portion of the holdings for this reporting manager are reported in this report and a portion are reported by other reporting manager(s).) List of Other Managers Reporting for this Manager: Form 13F File Number Name 28-4545 Berkshire Hathaway Inc.