AMENDMENT TO SHARE EXCHANGE AGREEMENT

Exhibit 4.5

AMENDMENT TO SHARE EXCHANGE AGREEMENT

               This AMENDMENT TO SHARE EXCHANGE AGREEMENT (this “Amendment”) is dated as of December 22, 2003 by and among Liberty Media Corporation, a Delaware corporation (“Liberty”), and each of the Persons, severally and not jointly, set forth on the signature pages hereto as Stockholders (the “Stockholders”).

RECITALS

               A.           Liberty and the Stockholders are parties to a Share Exchange Agreement dated as of August 18, 2003 (the “Agreement”).  Capitalized terms used but not otherwise defined in this Amendment have the respective meanings set forth in the Agreement.

               B.           Liberty and the Stockholders desire to amend the Agreement as set forth in this Amendment.

AGREEMENT

               In consideration of the foregoing recitals and the mutual promises made herein, and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto, intending to be legally bound, hereby agree as follows:

               1.            Amendments to Agreement.  The Agreement is hereby amended as follows:

               (a)          Section 2.1 of the Agreement is hereby amended to read, in its entirety, as follows:

“2.1        Closing Date.  The closing of the Exchange (the “Closing”) shall take place at 9:00 a.m. on the later of (a) January 5, 2004 and (b) the third business day following the date that all conditions thereto as specified in Section 5 and 6 have been satisfied or validly waived, at the offices of Holme Xxxxxxx & Xxxx LLP, 0000 Xxxxxxx Xxxxxx, Xxxxx 0000, Xxxxxx, Xxxxxxxx 00000, or at such other time or place as Liberty and the Deciding Stockholders may mutually agree (such date is hereinafter referred to as the “Closing Date”).”

               (b)          Section 7.1 of the Agreement is hereby amended to replace each occurrence of “December 31, 2003” therein with “January 31, 2004”.

               (c)          Exhibit A is hereby amended so that the total number of Liberty Shares reflected in the final column of the table therein shall be equal to “12,576,968”.

               (d)          The proviso at the end of the final sentence of Section 9 of Exhibit B to the Agreement (the “New Standstill Agreement”) is hereby amended to read, in its entirety, as follows: “provided that, (a) United’s obligations under the final sentence of Section 9(b) of the Old Standstill Agreement shall survive the execution and delivery

hereof and the termination of the Old Standstill Agreement and (b) Sections 7B and the related definitions in Section 1 shall survive the execution and delivery hereof and the termination of the Old Standstill Agreement as set forth in, and as modified by, the letter agreement, dated November 12, 2003, between Liberty (on behalf of each of the Liberty Parties (as defined in the Old Standstill Agreement)) and United.”

               2.            Effect of Amendment.  Except as expressly modified hereby, the Agreement will continue in full force and effect in accordance with its terms.  Any future reference to the Agreement will be deemed to be a reference to the Agreement as amended hereby.

               3.            Governing Law.  This Amendment will be governed in all respects by the laws of the State of Colorado, without giving effect to the conflicts of laws principles thereof.

               4.            Counterparts; Facsimile Copies.  This Amendment may be executed in any number of counterparts, each of which will be an original, and all of which together will constitute one instrument.  Facsimile copies hereof may be signed as counterpart originals.

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This Amendment is hereby executed as of the date first above written.

LIBERTY:
Liberty Media Corporation
By:		/s/ Xxxxxxxxx X. Xxxxxxxx
		Name: Xxxxxxxxx X. Xxxxxxxxx
		Title: Senior Vice President

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STOCKHOLDERS:		X. Xxxxxxxxx Holdings, LLLP
/s/ Xxxx X. Xxxxxxxxx		By:		/s/ Xxxx X. Xxxxxxxxx
Xxxx X. Xxxxxxxxx				Name: Xxxx X. Xxxxxxxxx
				Title: Executive Director

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		The GWS Trust
		By:
Xxxx X. Xxxxxx				Name: Xxxx X. Xxxxxx
				Title: Trustee

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Xxxxxxxx Limited Partnership				Xxxxxxxx Investment Limited Partnership
By:				By:
		Name: Xxxxxx X. Xxxxxxxx				Name: Xxxxxx X. Xxxxxxxx
		Title: Attorney-in-Fact				Title: Attorney-in-Fact
		Xxx Xxxxxxxx				Xxxxxxxx Xxxxx
		By Xxxxxx X. Xxxxxxxx, Attorney-in-Fact				By Xxxxxx X. Xxxxxxxx, Attorney-in-Fact
		Xxxxx Xxxxxxx Xxxx
		By Xxxxxx X. Xxxxxxxx, Attorney-in-Fact

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Xxxxxx & Xxxxxxx Company				Xxxxxxx Company
By:		/s/ Xxxxxx X. Xxxxxxx, Xx.		By:		/s/ Xxxxxx X. Xxxxxxx, Xx.
		Name: Xxxxxx X. Xxxxxxx, Xx.				Name: Xxxxxx X. Xxxxxxx, Xx.
		Title: Attorney-in-Fact				Title: Attorney-in-Fact
Xxxxx X. Xxxxxxx Living Trust				Xxxx X. Xxxxxxx Living Trust
By:		/s/ Xxxxxx X. Xxxxxxx, Xx.		By:		/s/ Xxxxxx X. Xxxxxxx, Xx.
		Name: Xxxxxx X. Xxxxxxx, Xx.				Name: Xxxxxx X. Xxxxxxx, Xx.
		Title: Attorney-in-Fact				Title: Attorney-in-Fact

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