- Aleksandar Katancevic
- Aleskandar Aleksandrov
- Angel Dimitrov
- Assoc. prof. dr Todor Trifonov
- Assoc. prof. Efrosima Zaneva-Dobranova
- Assoc. Prof. Georgi Nikolov
- Captain Branimir Trifonov
- CERB - Center for control of metals Ltd.
- CNG Ecogas AD
- Dimcho Syarov
- Emil Tsanov
- Eng. Marin Marinov
- Galco AD
- Gas-energy company - Elin Pelin Ltd.
- Gasstroymontaj AD
- Gastec BG AD
- Georgi Jaigarov
- Homegas Ltd.
- HTI Bulgaria
- Infrastroeji Ltd.
- Kameno Gas Ltd.
- Krum Hristov
- Luben Karatotev
- Lubomir Denchev
- Lubtcho Rusev
- Luchezar Georgiev
- Malin Ezekiev
- Mario Karadjov
- Martin Bojadzhiev
- Milen Kehayov
- Miloslav Katsarov
- Nayden Petkov
- Nikolai Zanev
- Nikolay Pavlov
- Outdoor Trading Ltd.
- Overgas Direct Ltd.
- Overgas Zapad AD
- Penko Efremov
- Petar Tsibranski
- Plastec Ltd.
- Prof. Vasil Balinov
- Rosen Zagorov
- Rusi Slavov
- Slav Nikolov
- Svetoslav Ivanov
- Svilengrad-gaz AD
- The University of Mining and Geology “St. Ivan Rilski”
- Tobogas Ltd.
- Toplomax Ltd.
- Vestitel BG AD
- „AQUASTAR-SYS" OOD