Arezzo:

Octocom
Octopus Energy Group
Oliver James Associates Ltd.
omnia retail
Omnissa (Italy) S.r.l.
Oncode
OneOcean Group
OneStream Software LLC
oneway promotion
Onyx Technology S.r.L.
Opdenergy
Open Smart Services
Open-Xchange Inc.
openjobmetis
Openjobmetis SpA
OPLIUM
OralPro
Orbyta Group
Orchard Robotics
orienta
orienta filiale di montevarchi
Orienta SPA
Out in Science, Technology, Engineering, and Mathematics
OutSystems, Inc.
OVERTECH Consulting
OVS S.p.A.
Oxford Instruments
Oxigent Technologies