1
Exhibit 21
THE WILLIAMS COMPANIES, INC. & AFFILIATES
March 23, 1994
Percent
Jurisdiction Owned by
of Immediate
Incorporation Parent
------------- ------
The Williams Companies, Inc. . . . . . . . . . . . . . . . . . . . . . . Delaware
Apco Argentina Inc. . . . . . . . . . . . . . . . . . . . . . . . . . Cayman Islands 62.60%
Apco Properties Ltd. . . . . . . . . . . . . . . . . . . . . . . . . Cayman Islands 100%
Kern River Gas Supply Corporation . . . . . . . . . . . . . . . . . . Delaware 50%
Kern River Service Corporation . . . . . . . . . . . . . . . . . . . . Delaware 50%
Langside Limited . . . . . . . . . . . . . . . . . . . . . . . . . . . Bermuda 100%
Northwest Pipeline Corporation . . . . . . . . . . . . . . . . . . . . Delaware 100%
Northwest Exploration Company . . . . . . . . . . . . . . . . . . . . Delaware 100%
Realco Realty Corp. . . . . . . . . . . . . . . . . . . . . . . . . . Delaware 100%
Realco of Crown Center, Inc. . . . . . . . . . . . . . . . . . . . . Delaware 100%
Realco of San Antonio, Inc. . . . . . . . . . . . . . . . . . . . . Delaware 100%
Realco Realty Developments, Inc. . . . . . . . . . . . . . . . . . . Delaware 100%
Tulsa Williams Company . . . . . . . . . . . . . . . . . . . . . . . . Delaware 100%
Willco, Inc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Delaware 100%
Williams Acquisition Holding Company, Inc. . . . . . . . . . . . . . . New Jersey 100%
Agrico Foreign Sales Corporation . . . . . . . . . . . . . . . . . . Guam 100%
Fishhawk Ranch, Inc. . . . . . . . . . . . . . . . . . . . . . . . . Florida 100%
Texasgulf Inc. . . . . . . . . . . . . . . . . . . . . . . . . . . . Delaware 15%
Williams Arkoma Corporation . . . . . . . . . . . . . . . . . . . . . Delaware 100%
Williams Energy Company . . . . . . . . . . . . . . . . . . . . . . . Delaware 100%
Williams Energy Ventures, Inc. . . . . . . . . . . . . . . . . . . . . Delaware 100%
Carbon County UCG, Inc. . . . . . . . . . . . . . . . . . . . . . . Delaware 100%
F T & T, Inc. . . . . . . . . . . . . . . . . . . . . . . . . . . . Delaware 100%
Williams Brokering Services, Inc. . . . . . . . . . . . . . . . . . Delaware 100%
Williams Energy Brokering Company . . . . . . . . . . . . . . . . . Delaware 100%
Williams Energy Derivatives and Trading Company . . . . . . . . . . Delaware 100%
Williams Energy Systems Company . . . . . . . . . . . . . . . . . . Delaware 100%
Williams Knowledge Systems, Inc. . . . . . . . . . . . . . . . . . . Delaware 100%
Williams Producer's Services Company . . . . . . . . . . . . . . . . Delaware 100%
Williams Exploration Company . . . . . . . . . . . . . . . . . . . . . Delaware 100%
Rainbow Resources, Inc. . . . . . . . . . . . . . . . . . . . . . . Colorado 100%
Williams Field Services Group, Inc. . . . . . . . . . . . . . . . . . Delaware 100%
NGL Production Company . . . . . . . . . . . . . . . . . . . . . . . Utah 100%
Williams CNG Company . . . . . . . . . . . . . . . . . . . . . . . . Delaware 100%
Williams Field Services - Mid-Continent Region Company . . . . . . . Delaware 100%
Williams Field Services - Rocky Mountain Region Company . . . . . . Utah 100%
Williams Gas Company . . . . . . . . . . . . . . . . . . . . . . . . Delaware 100%
Williams Gas Management Company . . . . . . . . . . . . . . . . . . Delaware 100%
Williams Gas Marketing Company . . . . . . . . . . . . . . . . . . . Delaware 100%
Williams Gas Processing - Blanco, Inc. . . . . . . . . . . . . . . . Delaware 100%
Williams Gas Processing Company . . . . . . . . . . . . . . . . . . Delaware 100%
Williams Gas Processing - Mid-Continent Region Company . . . . . . . Delaware 100%
Williams Gas Processing - Wamsutter Company . . . . . . . . . . . . Delaware 100%
Williams Gas Supply Company . . . . . . . . . . . . . . . . . . . . Delaware 100%
Williams Power Company . . . . . . . . . . . . . . . . . . . . . . . Delaware 100%
Williams Power Investments, Inc. . . . . . . . . . . . . . . . . . . Delaware 100%
Williams Power Services, Inc. . . . . . . . . . . . . . . . . . . . Delaware 100%
Williams Production Company . . . . . . . . . . . . . . . . . . . . Delaware 100%
Williams Washington Power Services, Inc. . . . . . . . . . . . . . . Delaware 100%
2
Percent
Jurisdiction Owned by
of Immediate
Incorporation Parent
------------- ------
Williams Information Services Corporation . . . . . . . . . . Delaware 100%
Williams Natural Gas Company . . . . . . . . . . . . . . . . Delaware 100%
Williams Gathering Company . . . . . . . . . . . . . . . . Delaware 100%
Willams Pipe Line Company . . . . . . . . . . . . . . . . . . Delaware 100%
WillBros Terminal Company . . . . . . . . . . . . . . . . . Delaware 100%
Williams Terminals Company. . . . . . . . . . . . . . . . . Delaware 100%
Williams Relocation Services, Inc . . . . . . . . . . . . . . Delaware 100%
Williams Storage Company . . . . . . . . . . . . . . . . . . Delaware 100%
Williams Telecommunications Group, Inc. . . . . . . . . . . . Delaware 100%
WilTel Communications Systems, Inc . . . . . . . . . . . . Delaware 100%
Facilities Communications International . . . . . . . . . Texas (Partnership) 50%
WCS, Inc . . . . . . . . . . . . . . . . . . . . . . . . Delaware 100%
WCS Microwave Services, Inc . . . . . . . . . . . . . . . Nevada 100%
Vyvx, Inc . . . . . . . . . . . . . . . . . . . . . . . . Delaware 100%
WilTel Data Network Services, Inc . . . . . . . . . . . . . Delaware 100%
WilTel Financial Corporation. . . . . . . . . . . . . . . . Delaware 100%
WilTel, Inc . . . . . . . . . . . . . . . . . . . . . . . . Delaware 100%
WilTel of New Hampshire, Inc. . . . . . . . . . . . . . . New Hampshire 100%
WilTel of Virginia, Inc . . . . . . . . . . . . . . . . . Virginia 100%
WilTel International, Inc . . . . . . . . . . . . . . . . . Delaware 100%
WilTel Undersea Cable, Inc. . . . . . . . . . . . . . . . . Delaware 100%
Williams Western Holding Company, Inc . . . . . . . . . . . . Delaware 100%
Northwest Alaskan Pipeline Company . . . . . . . . . . . . Delaware 100%
Northwest Argentina Corporation . . . . . . . . . . . . . . Utah 100%
Northwest Border Pipeline Company . . . . . . . . . . . . . Delaware 100%
Northern Border Pipeline Company . . . . . . . . . . . . Texas (Partnership) 12.25%
Northwest Land Company . . . . . . . . . . . . . . . . . . Delaware 100%
Williams Western Pipeline Company . . . . . . . . . . . . . . Delaware 100%
Kern River Gas Transmission Company . . . . . . . . . . . . Texas (Partnership) 50%