Ari Juhani Siponmaa

Equity holdings (3)

Companies in which this person holds a stake.

• Ecocoal OÜ33.32%

  Osaühing163844970 €since 2023-09-01
• Reval Engineering OÜ10.00%

  Osaühing16330320since 2023-09-02
• Mereo Group OÜ1.31%

  Osaühing12438776131.2 k €since 2023-09-02

Active roles (1)

• Greenup Carbon Tech OÜ — Juhatuse liige (since 2025-10-27)

Co-directors (1)

People who currently serve on the same boards. Sorted by number of shared companies.

• Helen Arme1 shared companyGreenup Carbon Tech OÜ

Co-investors (2)

People who hold equity in the same companies. Sorted by number of shared stakes.

• Juha Heikki Kalevi Häkkänen2 shared companiesEcocoal OÜ · Reval Engineering OÜ
• Ilmar Virolainen1 shared companyReval Engineering OÜ

Data sources

• Estonian Business Register (RIK)updated daily