SERO AS
SERO AS is registered as a limited company in Asker, Akershus with organisation number 912228738. The business is classified under manufacture of pharmaceutical preparations (NACE 21.200). The company was incorporated in 1963 and has 76 registered employees. Registered share capital is NOK 10.0m, divided into 100000 shares. The company's stated purpose is: “Produksjon, distribusjon og salg av kontrollsera, reagenser og instrumenter til bruk i analysevirksomhet i medisinske og andre laboratorier.”. The most recent filed accounts, for the 2025 financial year, show NOK 211.3m in revenue and NOK 53.9m in operating profit.
Key figures · 2025
Financial health · 2025
Who owns SERO AS?
SERO AS has 5 registered shareholders:
- Knut Weydahl Eldjarn 50.5%
- Astrid Torunn Eldjarn 22.5%
- Knut Erik Weydahl Eldjarn 9.0%
- Camilla Eldjarn Huitfeldt 9.0%
- Eileen Eldjarn 9.0%
Frequently asked questions about SERO AS
Who owns SERO AS?
Knut Weydahl Eldjarn is the largest registered owner, with 50.5%.
What is the revenue of SERO AS?
SERO AS had revenue of NOK 211.3m in 2025.
Who is the general manager of SERO AS?
Jens Stefan Nicolai Kernstock is registered as general manager of SERO AS.
Where is SERO AS based?
SERO AS has its business address in Billingstad.
Source: Biztrac.no · Data from the Brønnøysund Register Centre and the Norwegian Tax Administration · Last updated 03.10.2026.