Exhibit 21 SUBSIDIARIES OF THE REGISTRANT
Percentage of Voting Securities Owned By Immediate Parent as of August 31, 1996 ------------------- Parent of the Registrant Robert L. Parker 6% of Common Stock (6% of voting securities assuming full dilution) Consolidated subsidiaries of the Registrant (Jurisdiction of incorporation): Parker Drilling Company of South America, Inc. (Oklahoma) 100% Parker Drilling Company of Oklahoma, Inc. (Oklahoma) 100% Parker Technology, Inc. (Oklahoma) (1) 100% Vance Systems Engineering, Inc. (Texas) (2) 100% Parker Drilling Company International Limited (Nevada) (3) 100% Parker Drilling Company of Alaska Limited (Alaska) 100% Parker Drilling Company of New Guinea, Inc. (Oklahoma) 100% Parker Drilling Company of North America, Inc. (Oklahoma) 100% Parker Drilling Company Limited (Nevada) 100%
Certain subsidiaries have been omitted from the list since they would not, even if considered in the aggregate, constitute a significant subsidiary. All subsidiaries are included in the consolidated financial statements. - - ------------------------------------------------------------------------------ (1) Parker Technology, Inc. owns 100% of three subsidiary corporations, namely: Parco Masts and Substructures, Inc. (Oklahoma) O.I.M.E. Export Corporation (Texas) O.I.M.E. International, Inc. (Texas) (2) Vance Systems Engineering, Inc. owns 100% of Parker Drilling Company Limited (Bahamas), 100% of Parker Drilling Company Kuwait, Ltd. (Bahamas) and 93% of Parker Drilling Company Eastern Hemisphere, Ltd. (Oklahoma). Parker Drilling Company Limited owns 7% of Parker Drilling Company Eastern Hemisphere, Ltd. (Oklahoma). (3) Parker Drilling Company International Limited owns 100% of three subsidiary corporations, namely: Parker Drilling U.S.A. Ltd. (Nevada) Choctaw International Rig Corp. (Nevada) (which owns 100% of the common stock of Parker Drilling Company of Indonesia, Inc. (Oklahoma)) Creek International Rig Corp. (Nevada)