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| ABILDSØ ELEKTRISKE AS | 937794878 | OSLO |
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| ABL BYGG AS | 997934490 | ÅLESUND |
| ABMAS ELEKTRO AS | 986361642 | LØRENSKOG |
| Å-BØGG AS | 919383151 | ORKLAND |
| ABO OPPMÅLING AS | 897978032 | ASKER |
| ABO PLAN & ARKITEKTUR AS | 879951542 | BJØRNAFJORDEN |
| ABO PLAN & ARKITEKTUR STORD AS | 917495637 | STORD |
| ABORA PROSJEKT AS | 982753589 | BERGEN |
| ABOT AS | 915331262 | TØNSBERG |
| ABP ELEKTRO AS | 998583470 | ARENDAL |
| ABRAHAMSEN TORE | 970046666 | KRAGERØ |
| ABRAHAMSSON & HAUGSTVEDT AS | 983543847 | DRAMMEN |
| A. BRATVOLD | 923061754 | HAMAR |
| A.B. RØR AS | 932257955 | HÅ |
| ABRS RØR SÆTRE AS | 899327632 | ASKER |
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| ABS INSTALLASJON AS | 998228433 | LARVIK |
| ABSOLUTT ARKITEKTUR AS | 997912454 | OSLO |
| ABSOLUTT RØRSERVICE Terje Vidar Rød | 883846532 | OSLO |
| ABS-TEKNIKK AS | 813184672 | TRONDHEIM |
| ABT BYGG AS | 993298166 | FÆRDER |
| A.C BYGG AS | 932163756 | SARPSBORG |
| ACCIONA CONSTRUCCION S.A. | 914890519 | OSLO |
| ACEL AS | 988233315 | ÅLESUND |
| ACO ANLEGG AS | 996342778 | HARAM |
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| ACTIVE ELEKTRO AS | 913552113 | SANDNES |
| ADAM BYGG AS | 922036896 | OSLO |
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| ADAPTEO AS | 920954278 | DRAMMEN |
| AD ARKITEKTER AS | 894404302 | LIER |
| ADD ARKITEKTER AS | 979497997 | OSLO |
| ADELTON AS | 913731301 | ASKER |
| ADITUS AS | 923383433 | DRAMMEN |
| ADMOS BYGG AS | 925297372 | SOGNDAL |
| ÅDNEGARD JOHANN | 970103929 | GOL |
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| ADOLFSEN MASKIN OG TRANSPORT AS | 997040902 | SENJA |
| AD PROSJEKT BYGG AS | 996494225 | LIER |
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| ADR ELEKTRO AS | 995981661 | OSLO |
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| ADVANSIA AS | 883889762 | OSLO |
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| AF DECOM AS | 992097442 | OSLO |