Øystein Eftevaag is a private shareholder. Øystein Eftevaag holds a stake in 1 company.

Companies Øystein Eftevaag owns

Company	Stake	Value (est.)
ADBONANZA AS	41.2%	–

Source: Biztrac.no · Data from the Brønnøysund Register Centre and the Norwegian Tax Administration · Last updated 02.09.2026.