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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D. C. 20549

FORM 11-K

ý
ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 [FEE REQUIRED]
For the fiscal year ended December 31, 2003

OR

o
TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 [NO FEE REQUIRED]
For the transition period from            to            

Commission file number 0-20421

LIBERTY MEDIA 401(k) SAVINGS PLAN
(Full title of the Plan)

LIBERTY MEDIA CORPORATION
(Issuer of the securities held pursuant to the Plan)

12300 Liberty Boulevard
Englewood, Colorado 80112
(Address of its principal executive office)



REQUIRED INFORMATION

 
  Page No.
Financial Statements:    
 
Report of Independent Registered Public Accounting Firm

 

1
 
Statements of Net Assets Available for Participant Benefits, December 31, 2003 and 2002

 

2
 
Statements of Changes in Net Assets Available for Participant Benefits, Years ended December 31, 2003 and 2002

 

3-4
 
Notes to Financial Statements, December 31, 2003 and 2002

 

5-8
 
Schedule 1—Schedule H, Line 4i—Schedule of Assets (Held at End of Year), December 31, 2003

 

9
 
Schedule 2—Schedule H, Line 4a—Schedule of Nonexempt Transactions, Year ended December 31, 2003

 

10
 
Schedule 3—Schedule H, Line 4j—Schedule of Reportable Transactions, Year ended December 31, 2003

 

11

Exhibits—

 

 
 
23—Consent of KPMG LLP

 

 


SIGNATURE

        Pursuant to the requirements of the Securities Exchange Act of 1934, the members of the Plan Committee have duly caused this annual report to be signed on its behalf by the undersigned hereunto duly authorized.


 

 

LIBERTY MEDIA 401(k) SAVINGS PLAN
(Name of Plan)

 

 

By:

 

/s/  
ROBERT R. BENNETT      
Robert R. Bennett
Member of Plan Committee

June 8, 2004



Report of Independent Registered Public Accounting Firm

The Plan Committee
Liberty Media 401(k) Savings Plan:

        We have audited the accompanying statements of net assets available for participant benefits of the Liberty Media 401(k) Savings Plan (the Liberty Plan) as of December 31, 2003 and 2002, and the related statements of changes in net assets available for participant benefits for the years then ended. These financial statements are the responsibility of the Liberty Plan's management. Our responsibility is to express an opinion on these financial statements based on our audits.

        We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements. An audit also includes assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. We believe that our audits provide a reasonable basis for our opinion.

        In our opinion, the financial statements referred to above present fairly, in all material respects, the net assets available for participant benefits of the Liberty Plan as of December 31, 2003 and 2002, and the changes in net assets available for participant benefits for the years then ended in conformity with accounting principles generally accepted in the United States of America.

        Our audits were performed for the purpose of forming an opinion on the basic financial statements taken as a whole. The supplemental schedules of assets held at end of year, nonexempt transactions, and reportable transactions are presented for the purpose of additional analysis and are not a required part of the basic financial statements but are supplementary information required by the Department of Labor's Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974. These supplemental schedules are the responsibility of the Liberty Plan's management. The supplemental schedules have been subjected to the auditing procedures applied in the audits of the basic financial statements and, in our opinion, are fairly stated in all material respects in relation to the basic financial statements taken as a whole.

    KPMG LLP

Denver, Colorado
May 17, 2004

1



LIBERTY MEDIA 401(k) SAVINGS PLAN

Statements of Net Assets Available

for Participant Benefits

December 31, 2003 and 2002

 
  2003
  2002
 
  amounts in thousands

Contributions Receivable:          
  Participant   $ 241  
  Employer     83  
   
 
      324  
Nonparticipant-directed investments, at fair value:          
  Liberty Media Stock Fund (notes 1 and 2)     41,982   26,281
Participant-directed investments (notes 1 and 2):          
  Liberty Media Stock Fund     12,096   9,115
  Mutual funds     72,176   54,117
   
 
      84,272   63,232
   
 
Participant loans (note 2)     2,146   2,057
   
 
Net assets available for participant benefits   $ 128,724   91,570
   
 

See accompanying notes to financial statements.

2



LIBERTY MEDIA 401(k) SAVINGS PLAN

Statement of Changes in Net Assets Available

for Participant Benefits

Year ended December 31, 2003

 
  Participant
Directed
Investments

  Nonparticipant
Directed
Investments

  Total
 
 
  amounts in thousands

 
Contributions:                
  Employer   $   8,674   8,674  
  Participant     13,939     13,939  
  Rollovers     743     743  
   
 
 
 
      14,682   8,674   23,356  
   
 
 
 
Repayments of participant loans     (208 ) 208    
Net investment income:                
  Net appreciation of fair value of investments     11,560   9,327   20,887  
  Interest and dividend income     1,205   23   1,228  
   
 
 
 
      12,765   9,350   22,115  
   
 
 
 
Total contributions and net investment income     27,239   18,232   45,471  
Administrative expenses     (39 ) (4 ) (43 )
Loans to participants     346   (346 )  
Distributions to participants     (6,176 ) (2,098 ) (8,274 )
   
 
 
 
Increase in net assets available for participant benefits     21,370   15,784   37,154  
Net assets available for participant benefits:                
  Beginning of year     65,289   26,281   91,570  
   
 
 
 
  End of year   $ 86,659   42,065   128,724  
   
 
 
 

See accompanying notes to financial statements.

3



LIBERTY MEDIA 401(k) SAVINGS PLAN

Statement of Changes in Net Assets Available

for Participant Benefits

Year ended December 31, 2002

 
  Participant
Directed
Investments

  Nonparticipant
Directed
Investments

  Total
 
 
  amounts in thousands

 
Contributions:                
  Employer   $   8,435   8,435  
  Participant     13,857     13,857  
  Rollovers     1,361     1,361  
   
 
 
 
      15,218   8,435   23,653  
   
 
 
 
Repayments of participant loans     (127 ) 127    
Net investment income (loss):                
  Net depreciation of fair value of investments     (14,343 ) (11,713 ) (26,056 )
  Interest and dividend income     1,097   245   1,342  
   
 
 
 
      (13,246 ) (11,468 ) (24,714 )
   
 
 
 
Total contributions and net investment income (loss)     1,845   (2,906 ) (1,061 )
Administrative expenses     (9 ) (4 ) (13 )
Loans to participants     207   (207 )  
Distributions to participants     (8,664 ) (2,736 ) (11,400 )
   
 
 
 
Decrease in net assets available for participant benefits     (6,621 ) (5,853 ) (12,474 )
Net assets available for participant benefits:                
  Beginning of year     71,910   32,134   104,044  
   
 
 
 
  End of year   $ 65,289   26,281   91,570  
   
 
 
 

See accompanying notes to financial statements.

4



LIBERTY MEDIA 401(k) SAVINGS PLAN

Notes to Financial Statements

December 31, 2003 and 2002

(1)   Summary of Significant Accounting Policies

Basis of Presentation

        The accompanying financial statements of the Liberty Media 401(k) Savings Plan (the "Liberty Plan") have been prepared on the accrual basis and present the net assets available for participant benefits and the changes in those net assets. The sponsor of the Liberty Plan is Liberty Media Corporation ("Liberty").

Trust Fund Managed by Fidelity Management Trust Company ("Trustee")

        Under the terms of a trust agreement between Liberty and the Trustee, the Trustee manages a trust fund on behalf of the Liberty Plan and has been granted authority concerning purchases and sales of investments for the trust fund. The Trustee may invest up to 100% of the assets of the Liberty Plan in employer securities without regard to any fiduciary requirement to diversify Liberty Plan assets. Additionally, the Liberty Plan is allowed to invest in non-employer securities.

Investments

        Investments are reflected in the accompanying financial statements at fair value. Fair value represents the closing prices for those securities having readily available market quotations, and fair value as determined by the Trustee with respect to other securities. The Liberty Media Stock Fund is a unitized fund that is measured in units rather than shares. The Liberty Media Stock Fund consists mostly of Liberty Series A common stock with an insignificant amount of cash or cash equivalents. The per share fair values used for investments in Liberty Series A common stock at December 31, 2003 and 2002 are $11.89 and $8.94, respectively. The foregoing prices are the closing market prices of Liberty Series A common stock on those dates. Changes in market values after the Liberty Plan's year end are not reflected in the accompanying financial statements.

        Securities and investment transactions are accounted for on the trade date. Distributions are priced at fair value and are accounted for when shares are transferred by the Trustee to participants. The cost basis of such shares distributed is determined using the average cost method. Dividend income is recorded on the ex-dividend date. Income from other investments is recorded as earned on an accrual basis.

Income Taxes

        The Internal Revenue Service (the "IRS") has determined and informed Liberty by a letter dated March 1, 2001, that the Liberty Plan and related trust are designed in accordance with applicable sections of the Internal Revenue Code ("IRC"). Once qualified, the Liberty Plan is required to operate in conformity with the IRC to maintain its qualification. The Liberty Plan administrator is not aware of any course of action or series of events that have occurred that might adversely affect the Liberty Plan's qualified status.

Use of Estimates

        The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the

5



date of the financial statements and the reported amounts of additions and deductions during the reporting period. Actual results could differ significantly from those estimates.

Plan Expenses

        Any employer contribution amounts forfeited may be used to pay plan expenses except for any fees related to loans, which are paid by participants. Any additional administrative expenses of the Liberty Plan are paid by Liberty.

(2)   Description of the Liberty Plan

        The following description of the Liberty Plan is provided for general information purposes only. Participants should refer to the plan document for more complete information.

General

        The Liberty Plan is a defined contribution plan sponsored by Liberty, which enables participating employees of Liberty and its qualifying subsidiaries to receive an interest in Liberty and to receive benefits upon retirement. Employees of Liberty and its 80% or more owned subsidiaries who are at least 18 years of age and (i) have worked at least three consecutive months or (ii) have completed one year of service (as defined in the Liberty Plan document) are eligible to participate in the Liberty Plan.

Contributions

        Participants, other than employees of Ascent Media Group and its eligible subsidiaries, may make (i) pre-tax contributions to the Liberty Plan of up to 75% of their compensation, as defined or (ii) after-tax contributions up to 10% of their compensation. Liberty and its subsidiaries, other than Ascent Media Group, make matching contributions equal to 100% of participant contributions, up to a maximum match of 10% of eligible compensation. Participants who are employees of Ascent Media Group may contribute up to 75% of their compensation, as defined, on a pre-tax basis or up to 15% of their compensation on an after-tax basis, to the Liberty Plan. Ascent Media Group may make matching contributions equal to $.50 for each $1.00 contributed by the participants up to a maximum match of 3% of eligible compensation. All participant contributions and employer matching contributions are subject to limitations as determined annually by the IRS. Employee pre-tax contributions and combined employee/employer contributions per participant were limited to $12,000 and $40,000, respectively, in 2003 and $11,000 and $40,000 respectively in 2002. Catch-up contributions, as defined in the Economic Growth and Tax Relief Reconciliation Act of 2001, are permitted for those eligible employees and are not matched by the employer. Through December 31, 2003, employer contributions were invested in the Liberty Media Stock Fund. Beginning January 1, 2004, participants who are fully vested in their employer contributions can direct the employer contributions to any investment in the Liberty Plan. Employer contributions for participants who are not fully vested continue to be invested in the Liberty Media Stock Fund only. Employee contributions may be invested in any investments in the Liberty Plan, including the Liberty Media Stock Fund. Liberty reserves the right to change the matching contribution amounts at any time.

Rollovers

        Participants may elect to rollover amounts from other qualified plans or individual retirement accounts into the Liberty Plan provided that certain conditions are met.

6



Participant Loans

        Participants may borrow from their fund accounts a minimum of $1,000 up to the lesser of $50,000 or 50% of their vested account balance. Loans, other than those transferred from other plans, must be repaid within five years and bear interest at a rate equal to prime rate in effect on the first day of the calendar quarter in which the loan is originated plus 1%. Loans transferred from other plans retain the repayment terms and interest rates in effect at the time of transfer. Loans are secured by the vested balance in the participant's account, and bear interest at rates ranging from 5% to 10.5% at December 31, 2003. Principal and interest are paid ratably through monthly payroll deductions.

Forfeitures

        Forfeitures of employer contributions (due to participants' termination prior to full vesting) are first used to pay Liberty Plan expenses, with any excess used to reduce Liberty's future matching contributions. Forfeitures aggregated approximately $274,000 and $216,000 during 2003 and 2002, respectively. Unused forfeitures aggregated approximately $787,000 and $398,000 at December 31, 2003 and 2002, respectively.

Investment Options

        As of December 31, 2003, the Liberty Plan has eighteen investment options including seventeen mutual funds and one unitized stock fund. The mutual funds are comprised of a money market mutual fund, two growth and income mutual funds, four growth mutual funds, two income mutual funds, a global growth mutual fund, an international growth mutual fund and six asset allocation funds based on target retirement dates. Plan participants may change investment options and contribution percentages on a daily basis.

Benefit Payments

        Distributions from the Liberty Plan may be made to a participant upon death, total disability, financial hardship or termination of employment. Distributions and other withdrawals are processed on a daily basis.

Vesting

        Participant contributions are always fully vested. Participants acquire a vested right in employer matching contributions, other than employer contributions transferred from other plans, as follows:

Years of service

  Vesting
percentage

 
Less than 1   0 %
1 year   33 %
2 years   66 %
3 years   100 %

        Employer matching contributions transferred from other plans vest according to the terms specified in the transferor plans.

7



Plan Termination

        Although Liberty has not expressed any intent to terminate the Liberty Plan, it may do so at any time, subject to the provisions of ERISA. The Liberty Plan provides for full and immediate vesting of all participant rights upon termination of the Liberty Plan.

(3)   Investments

        The fair value of individual investments that represent 5% or more of the Liberty Plan's net assets at December 31, 2003 and 2002 are as follows:

 
  Fair value at
December 31,

Investment

  2003
  2002
 
  amounts in thousands

Liberty Media Stock Fund   $ 54,078   35,396
Templeton Foreign A*   $ 6,490  
Janus Worldwide*   $   5,078
Fidelity Magellan   $ 22,676   18,981
Fidelity Equity Income   $ 9,367   6,200
Fidelity Investment Grade Bond   $ 7,047   7,160
Fidelity Retirement Money Market   $ 17,797   15,615

*
During the year ended December 31, 2003, the Liberty Plan committee removed the Janus Worldwide mutual fund as an investment option and replaced it with the Templeton Foreign A mutual fund.

(4)   Liberty Rights Offering

        During the fourth quarter of 2002, Liberty completed a rights offering pursuant to which existing shareholders, including the Liberty Plan and the Liberty Plan participants, received .04 transferable subscription rights to purchase shares of Liberty Series A common stock for each share of common stock held by them at the close of business on October 31, 2002. Liberty Plan participants could elect to exercise the rights attributable to the common stock in their accounts, or they could sell those rights through November 25, 2002. Because the rights were not "qualifying employer securities" under ERISA, the distribution of the rights to the Liberty Plan was a prohibited transaction under ERISA. Effective November 14, 2003, the Department of Labor issued a Prohibited Transaction Exemption with respect to the Liberty rights offering.

(5)   Subsequent Event

        Effective June 7, 2004, Liberty effected the spin off (the "Spin Off") of its international subsidiary, Liberty Media International, Inc. ("LMI"), by means of a distribution to Liberty's shareholders of all of the shares of common stock of LMI. Each Liberty shareholder, including the Liberty Media Stock Fund, received .05 shares of LMI common stock for each share of Liberty common stock held. In connection with the Spin Off, the Liberty Plan was amended to allow participants to invest in a unitized stock fund, which will hold LMI common stock.

8


Schedule 1


LIBERTY MEDIA 401(k) SAVINGS PLAN

Schedule H, Line 4i—Schedule of Assets (Held at End of Year)

December 31, 2003

Identity of
issuer

  Description of investment
including par value

  Fair value
 
   
  amounts in thousands

Liberty Media Corporation   Series A common stock, par value $.01 per share (historical cost basis—$40,842,000)   $ 54,078

Templeton

 

Templeton Foreign A

 

 

6,490

Spartan

 

Spartan 500 Index Fund

 

 

1,262

Pacific Investment Management Co. 

 

PIMCO High Yield Fund—Administrative Class

 

 

641

Baron

 

Baron Growth

 

 

1,335

Fidelity

 

Fidelity Magellan

 

 

22,676

Fidelity

 

Fidelity Equity Income

 

 

9,367

Fidelity

 

Fidelity Investment Grade Bond

 

 

7,047

Fidelity

 

Fidelity Retirement Money Market

 

 

17,797

Fidelity

 

Fidelity Overseas

 

 

525

Fidelity

 

Fidelity Blue Chip Growth

 

 

1,022

Fidelity

 

Fidelity Low-Priced Stock

 

 

2,234

Fidelity

 

Fidelity Freedom Income

 

 

94

Fidelity

 

Fidelity Freedom 2000

 

 

167

Fidelity

 

Fidelity Freedom 2010

 

 

430

Fidelity

 

Fidelity Freedom 2020

 

 

787

Fidelity

 

Fidelity Freedom 2030

 

 

253

Fidelity

 

Fidelity Freedom 2040

 

 

49

Participant loans

 

Interest rates ranging from 5.00% to 10.5%

 

 

2,146

 

 

 

 



 

 

 

 

$

128,400

 

 

 

 


        All investments are held by Fidelity Management Trust Company, Inc., which is a party-in-interest. Liberty Media Corporation is the plan sponsor, which is a party-in-interest.

See accompanying report of independent registered public accounting firm.

9


Schedule 2


LIBERTY MEDIA 401(k) SAVINGS PLAN

Schedule H, Line 4a—Schedule of Nonexempt Transactions

Year Ended December 31, 2003

Identity of
party involved

  Relationship to plan employer
or other party-in-interest

  Description of transactions
including maturity date,
rate of interest collateral,
par or maturity value

 
Liberty Media 401(k) Savings Plan   Plan Sponsor   (1 )

(1)
An unintentional delay by a subsidiary of Liberty in submitting certain 2003 employee contributions that were withheld from employee paychecks to the trustee of the Liberty Plan, in the aggregate amount of $1,171, resulted in a prohibited transaction under ERISA. The delinquent deposit was remitted to the trustee after the time permitted by Department of Labor regulations. In 2004, Liberty reimbursed the Liberty Plan $104 for lost earnings and interest on the late deposit, so that the prohibited transaction has been corrected.

See accompanying report of independent registered public accounting firm.

10


Schedule 3


LIBERTY MEDIA 401(k) SAVINGS PLAN

Schedule H, Line 4j—Schedule of Reportable Transactions

Year Ended December 31, 2003

amounts in thousands

Identity of
party involved

  Description
of asset

  Purchase
Price

  Selling
Price

  Cost of
Asset

  Net gain
or (loss)

Liberty Media Corporation*   Liberty Series A common stock, par value $.01 per share   $ 8,591      

*
Denotes party-in-interest

See accompanying report of independent registered public accounting firm.

11



EXHIBIT INDEX

Shown below are the exhibits which are filed or furnished as a part of this Report—

        23—Consent of KPMG LLP




QuickLinks

SIGNATURE
Report of Independent Registered Public Accounting Firm
LIBERTY MEDIA 401(k) SAVINGS PLAN Statements of Net Assets Available for Participant Benefits December 31, 2003 and 2002
LIBERTY MEDIA 401(k) SAVINGS PLAN Statement of Changes in Net Assets Available for Participant Benefits Year ended December 31, 2003
LIBERTY MEDIA 401(k) SAVINGS PLAN Statement of Changes in Net Assets Available for Participant Benefits Year ended December 31, 2002
LIBERTY MEDIA 401(k) SAVINGS PLAN Notes to Financial Statements December 31, 2003 and 2002
LIBERTY MEDIA 401(k) SAVINGS PLAN Schedule H, Line 4i—Schedule of Assets (Held at End of Year) December 31, 2003
LIBERTY MEDIA 401(k) SAVINGS PLAN Schedule H, Line 4a—Schedule of Nonexempt Transactions Year Ended December 31, 2003
LIBERTY MEDIA 401(k) SAVINGS PLAN Schedule H, Line 4j—Schedule of Reportable Transactions Year Ended December 31, 2003 amounts in thousands
EXHIBIT INDEX