1

2

3

4

5

6

AbuDhabiNationalOilCompany

7

AMSOIL

8

Anadarko Petroleum

9

AnTech

10

Apache

11

Arch Petroleum

12

ARCO

13

Asea Brown Bovari

14

Ballistic Energy

15

Belray Lubricants

16

Blue Dolphin Energy

17

BP Amoco

18

Brooklyn Union

19

British Gas

20

Burlington Resources

21

Cabot Oil & Gas

22

Cambrian Group

23

Canadian 88 Energy Corp.

24

Chauvco Resources

25

Chevron

26

China National Petroleum Corporation(CNPC)

27

Chinese Petroleum Corporation

28

CLI International

29

Conoco

30

Cotton Valley Resources

31

Crestar Energy

32

Cross Timbers Oil Company

33

Danoil Energy

34

Diamond Geophysical

35

DuPont Performance Lubricants

36

Eaton Industries

37

Eckel

38

Edgehill Exploration

39

Elf Aquitaine

40

Empresa Colombiana de Petroleos (ECOPETROL)

41

Energie-Versorgung Schwaben AG

42

Eni S.p.A. (AGIP)

43

Enterprise Oil plc

44

Exxon

45

Fletcher Challenge Energy

46

Fuchs Lubricants

47

Global Marine

48

Grenley Stewart Resources

49

Gulf Stream Resources

50

Hegyi GeoTechnologies International Inc.

51

Hindustan Petroleum Corporation Limited

52

S.A. Holditch and Associates

53

J. M. Huber Corporation

54

Idemitsu Kosan Co. Ltd.

55

IKODA

56

John Sharry

57

JP Oil

58

KN Energy

59

Korea National Oil Company

60

Kuwait National Petroleum Company

61

LASMO plc

62

Lexam Explorations

63

Louis Dreyfus Natural Gas

64

Lubriplate Lubricants

65

Marathon Oil

66

Mobil

67

Mosaic Oil

68

National-Oilwell

69

Norsk Hydro

70

Northern PetroSearch

71

Nuevo Energy

72

PanCanadian Petroleum Limited

73

Parker Drilling

74

Pennzoil

75

Perez Companac S.A.

76

Petrobras

77

Phillips Petroleum Company

78

PIRA Energy Group

79

Place Resources

80

Premier Oil

81

Rocky Mountain Exploration

82

Ruwco Oil and Gas Corporation

83

Saga Petroleum ASA

84

Scotia Group

85

Shell Group

86

Simulation Sciences

87

South Jersey Industries, Inc.

88

Sperry-Sun Drilling Services

89

St. Mary Land and Exploration Company

90

Statoil

91

Syntron

92

Total

93

Toyo Engineering

94

Turkish Petroleum

95

Unocal

96

Utilicorp

97

UTSI International

98

Valvoline

99

Vital Visions

100

Weatherford

101

YPF S. A.

102

Zilkha Energy Company