„AURUBIS Bulgaria” AD, Pirdop

CPPE Carbon Process & Plant Engineering S.A., Luxembourg

„VEGA –Vurbenov” OOD, Sofia

“MP-Metalplast”AD, Pirdop

„KCM” AD, Plovdiv

„Alstom- Bilgaria” EOOD

ТРР„AES 3C Maritza East 1 EOOD”, Galabovo

“TPP Maritsa East 2” EAD

„Enel Produzione” SpA, Italy

ТРР “ConturGlobal Maritsa East 3” AD, Mednikarovo village

TPP „Bobov dol” EAD

TPP „Belhatov “ – Poland

„Kurotec-KTS”, Poland

Dundee Precious Metals Chelopech EAD, Chelopech village

“Chelopech Mining” EAD, Chelopech village

WWTP „Almagest” AD Sofia

”Vinprom Karnobat”

WTP „Vinsindustrys”, „Envirochemie” GmbH, Germany

WWTP „Fazerles”, Silistra, “Envirochemie”GmbH, Germany

„Envirochemie”, Germany

„Diana commerce 1” EOOD

STRABAG EAD

Kamenitza AD

GLOBAL WATER ENGINEERING GmbH, Germany

“ ISA 2000” EOOD Sofia

„Kurotec-KTS”, Germany

CBMI Construction Company LTD.- branch in Bulgaria, China