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FILED PURSUANT TO RULE 424(B)(3)
REGISTRATION NO. 333-86257
Supplement, Dated June 29, 2000, to Prospectus, Dated September 17, 1999, of
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UnitedGlobalCom, Inc.
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Additional Selling Securityholder. The following selling securityholder is 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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Donaldson, Lufkin & Jenrette Securities Corp......... 15,000 15,000
Donaldson, Lufkin & Jenrette Securities Corp. was an initial purchaser in the
June 1999 private placement offering through which the selling securityholders
acquired their shares, resulting in a material relationship between us and
Donaldson, Lufkin & Jenrette Securities Corp.
