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| Init Stavanger AS | Stavanger | 2014 |
| INIT4U Accounting AS | Trondheim | 2022 |
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| Initium Energy AS | Sandnes | 2019 |
| Initium Invest AS | Oslo | 2007 |
| Inizia Consulting AS | Vinterbro | 2022 |
| Inja Prosjekt AS | Bjørøyhamn | 2021 |
| Injection Bottle Development AS | Sandvika | 2010 |
| Injeksjonsutstyr AS | Evje | 2025 |
| Inju AS | Vikhammer | 2023 |
| Ink Media House AS | Oslo | 2025 |