- Enel S.p.a.
- Italferr S.p.a..
- Rete Ferriovaria Italiana S.p.a
- Slovenske Electracne
- Alstom Ferriovaria S.p.a.
- Ansaldo Hitachi
- Sirti S.p.a.
- Roma Metropolitane S.p.a.
- Balfour Beatty Rail S.p.a.
- ATAC S.p.a.
- KT Kinetics Technlogy S.p.a.
- PEG
- SAIPEM
- TECHNIPFMC S.p.a.
- BFIT s.r.l.
- SPEA Engineering
- ENEL Ingengeria e ricerca
- Bombardier Transportation
- Progetto 10
- ITI
- Gransolar Ghella s.r.l.
- Techproject s.r.l.
and other...