| Name | Type | Country |
|---|---|---|
| G93 Telecomunicaciones | Enterprise | Spain |
| Garaia | Enterprise | Spain |
| Genegis | Enterprise | Italy |
| GEOX TERINFORMATIKAI KFT | Enterprise | |
| Gerdau Aceros Especiales Europa | Enterprise | Spain |
| GiTy | Enterprise | Czech Republic |
| Gobierno de España | Public administration | Spain |
| Gobierno Vasco | Public administration | Spain |
| Grupo Innovati | Enterprise | |
| Grupo Santander de Investigación | Enterprise |