<Page>

                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                                    FORM 8-K
                                 CURRENT REPORT

                         Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

       Date of Report (date of earliest event reported): NOVEMBER 6, 2006

                            LIBERTY MEDIA CORPORATION
             (Exact name of registrant as specified in its charter)

           DELAWARE                       000-51990              84-1288730
(State or other jurisdiction of          (Commission          (I.R.S. Employer
incorporation or organization)           File Number)        Identification No.)

                               12300 LIBERTY BLVD.
                            ENGLEWOOD, COLORADO 80112
              (Address of principal executive offices and zip code)

       Registrant's telephone number, including area code: (720) 875-5400

Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions (see General Instruction A.2. below):

[ ]  Written communications pursuant to Rule 425 under the Securities Act (17
     CFR 230.425)

[ ]  Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17
     CFR 240.14a-12)

[ ]  Pre-commencement communications pursuant to Rule 14d-2(b) under the
     Exchange Act (17 CFR 240.14d-2(b))

[ ]  Pre-commencement communications pursuant to Rule 13e-4(c) under the
     Exchange Act (17 CFR 240.13e-4(c))

<Page>

ITEM 2.02.  RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On November 6, 2006, Liberty Media Corporation (the "Company") issued a press
release (the "Press Release") setting forth information, including financial
information regarding certain of its privately held assets, which supplements
the financial statements and related Management's Discussion and Analysis of
Financial Condition and Results of Operations contained in the Company's
Quarterly Report on Form 10-Q for the quarter ended September 30, 2006, which
was filed with the Securities and Exchange Commission (the "SEC") on November 6,
2006. The information included in the Press Release is not meant to serve as a
release of financial results of the Company.

This Form 8-K and the Press Release attached hereto as Exhibit 99.1, insofar as
they disclose historical information regarding the Company's results of
operations or financial condition for the quarter ended September 30, 2006, are
being furnished to the SEC under Item 2.02 of Form 8-K.

<Page>

                                    SIGNATURE

     Pursuant to the requirements of the Securities Exchange Act of 1934, as
amended, the registrant has duly caused this report to be signed on its behalf
by the undersigned hereunto duly authorized.

Date: November 6, 2006

                                        LIBERTY MEDIA CORPORATION


                                        By: /s/ Mark E. Burton
                                            -------------------------------
                                            Name:    Mark E. Burton
                                            Title:   Vice President