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| IB MASKIN AS | 994550144 | VOSS |
| IBO ARKITEKTUR AS | 933924114 | OSLO |
| I-BOLIG AS | 976746996 | ULLENSAKER |
| IBR INNSTALLASJON OG BYGGSERVICE AS | 981648196 | NORDRE FOLLO |
| IB RØRSERVICE AS | 931145274 | ELVERUM |
| I BYGG AS | 996013081 | TØNSBERG |
| ICC NORDEN AS | 821277302 | OSLO |
| IDAR NESE AS | 989082108 | ASKØY |
| IDÉHUS ÅLESUND AS | 991569405 | ÅLESUND |
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| IDEHUS MODUM AS | 996467023 | MODUM |
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| IDEHUS ØSTFOLDBYGG AS | 990092966 | INDRE ØSTFOLD |
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| IDÉHUS TRONDHEIM AS | 885832202 | TRONDHEIM |
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| ID RØR AS | 928806782 | OSLO |
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