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FILED PURSUANT TO RULE 424(b)(3)
REGISTRATION NO. 333-86257
Supplement, Dated March 3, 2000, to Prospectus, Dated September 17, 1999, of
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UnitedGlobalCom, Inc.
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Additional Selling Securityholders. The following selling securityholders are
added to the list of selling securityholders in the prospectus:
Number of Depositary Shares
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Name of Selling Securityholder Owned Offered
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Paloma Securities L.L.C. 44,000 44,000
Paloma Strategic Securities Limited 44,000 44,000
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March 3, 2000
Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C. 20549-1004
Re: UnitedGlobalCom, Inc.
Supplement, dated March 3, 2000, to Prospectus, dated September 17,
1999 (Registration Statement on Form S-3: File No. 333-86257)
Ladies and Gentlemen:
Pursuant to Rule 424(b)(3) under the Securities Act of 1933, as amended,
UnitedGlobalCom, Inc. (the "Company") herewith files a prospectus supplement,
dated March 3, 2000, to the Company's prospectus, dated September 17, 1999,
relating to the Company's Registration Statement on Form S-3 (File No. 333-
86257) with respect to depository shares each representing 1/20th of a share of
7% Series C Senior Cumulative Convertible Preferred Stock of the Company (the
"Preferred Stock"), shares of Class A common stock of the Company issuable upon
conversion of the Preferred Stock, and shares of Class A common stock of the
Company issuable as dividends on the Preferred Stock.
Very truly yours,
Hendrik F. Jordaan
