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Filed Pursuant to Rule 424(b)(3)
Registration No. 333-86257
Supplement, Dated May 11, 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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Chase Vista Growth & Income Fund............... 80,000 80,000
Morgan Stanley Dean Witter..................... 12,870 12,870
Salomon Smith Barney Inc....................... 86,500 86,500
Donaldson, Lufkin & Jenrette Securities Corp. . 1,237,130 1,237,130
Salomon Smith Barney Inc. and Donaldson, Lufkin & Jenrette Securities Corp. were
initial purchasers in the June 1999 private placement offering through which the
selling securityholders acquired their shares, resulting in material
relationships between us and the initial purchasers. Morgan Stanley Dean Witter
has served us an underwriter for certain of our other securities offerings,
resulting in a material relationship between us and Morgan Stanley Dean Witter.
