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Filed pursuant to Rule 424(b)(3)
Registration # 333-86257
Supplement, Dated December 10 , 1999, to Prospectus, Dated September 17, 1999,
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of 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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Salomon Smith Barney Inc....................... 115,120 115,120
Tribeca Investments L.L.C...................... 75,000 75,000
Salomon Smith Barney Inc., together with Donaldson, Lufkin & Jenrette Securities
Corporation and Goldman Sachs and Company, was an initial purchaser 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.
