| Oy Abilita Ab | Information & communication | 1990 |
| Oy Abilita Marketing Ab | Wholesale & retail | 1987 |
| Oy Alholmens Kraft Ab | Energy | 1997 |
| Oy Aluexbeams Ab | Manufacturing | 2017 |
| Oy Arne Stara Ab | Wholesale & retail | 1979 |
| Oy Aspel-Invest Ab | Real estate | 2004 |
| Oy Axab Ab | Wholesale & retail | 1991 |
| Oy BAS-Consulting Ab | Information & communication | 1987 |
| Oy BD-Möbel Ab | Wholesale & retail | 1994 |
| Oy Beck Hamn Ab | Real estate | 2007 |
| Oy Bevex Security Ab | Administrative & support | 2001 |
| Oy Bilhuset i Jakobstad Ab | Real estate | 2018 |
| Oy Botnia Holding Ab | Financial services | 1974 |
| Oy C & G Invest Ab | Financial services | 1988 |
| Oy CJB Backlund Ab | Other services | 2022 |
| Oy Citotest Ab | Health & social care | 1978 |
| Oy Conalin Ab | Wholesale & retail | 2002 |
| Oy Consaler Ab | Real estate | 1988 |
| Oy Creative PC Systems Ab | Information & communication | 1985 |
| Oy Danman Ab | Real estate | 1987 |
| Oy Ekointernet Ab | Information & communication | 2000 |
| Oy FR Valve Products Ab | Manufacturing | 2005 |
| Oy Farma-Medi Ab | Wholesale & retail | 2022 |
| Oy Fluid-Bag Ab | Manufacturing | 1963 |
| Oy Frontline Audio Ab | Arts & recreation | 2008 |
| Oy Fundamenta Nord Ab | Professional & scientific | 1994 |
| Oy GH Padel Ab | Arts & recreation | 2022 |
| Oy Granlund Capital Ab | Financial services | 2014 |
| Oy Graphics Jakobstad Ab | Manufacturing | 1992 |
| Oy Grönsiskans Värme Ab | Real estate | 1965 |
| Oy Herrfors Ab | Energy | 1937 |
| Oy Hilltip Ab | Wholesale & retail | 2020 |
| Oy Imatek Ab | Professional & scientific | 2013 |
| Oy Intercar-Center Ab | Wholesale & retail | 1994 |
| Oy J-LENC Ab | Professional & scientific | 2003 |
| Oy JAB Management Ab | Professional & scientific | 2009 |
| Oy JK Prospect Ab | Wholesale & retail | 2006 |
| Oy Jakobinvest Ab | Real estate | 1994 |
| Oy Jakobstads Business Center Ab | Real estate | 1987 |
| Oy Jakobstads Kubik Ab | Financial services | 1988 |
| Oy Jeppis Stadion Ab | Real estate | 2008 |
| Oy Josupek Ltd | Education | 1992 |
| Oy Jugend Home Hotel Ab | Hospitality | 2008 |
| Oy K1 Services Ab | Information & communication | 2003 |
| Oy KJ Plastpoint Ab | Manufacturing | 1980 |
| Oy Kedddy Markkinointi Ab | Wholesale & retail | 2000 |
| Oy Kust Car Ab | Other services | 1990 |
| Oy Kuusenjuuri Yhtiöt Ab | Administrative & support | 2024 |
| Oy LB Hyresbåt Ab | Transport & logistics | 2012 |
| Oy LE Management Ab | Professional & scientific | 1988 |
| Oy Last Drops Ab | Professional & scientific | 2007 |
| Oy Lederfrost | Real estate | 1935 |
| Oy Leif Wikar Ab | Financial services | 1988 |
| Oy MAMF Global Outreach Ltd | Professional & scientific | 2019 |
| Oy MKV Palvelut Ab | Financial services | 2011 |
| Oy Man & Horsepower Services Ltd | Professional & scientific | 2004 |
| Oy Medipunkt Service Ab | Health & social care | 2015 |
| Oy Midwest Invest Ab | Real estate | 1996 |
| Oy Mosha Ab | Other services | 2025 |
| Oy Nautor Ab | Manufacturing | 1989 |
| Oy North Shore Datacenter Ab | Information & communication | 2018 |
| Oy Nortours Ab | Professional & scientific | 1991 |
| Oy Novabotnia Ab | Information & communication | 2016 |
| Oy Novasec Ab | Information & communication | 1989 |
| Oy Offset-Print M. Johansson Ab | Manufacturing | 1988 |
| Oy PedeCon Ab | Construction | 2001 |
| Oy Permovärme Ab | Energy | 1971 |
| Oy Pietarsaaren Auto Tec Ab | Real estate | 1991 |
| Oy Pietec Ab | Construction | 1996 |
| Oy Pilonga Ab | Wholesale & retail | 2025 |
| Oy Pirilö Golfcenter Ab | Arts & recreation | 1989 |
| Oy Pohjanmaan Biokaasu - Österbottens Biogas Ab | Water & waste | 2009 |
| Oy Polishine Ab | Manufacturing | 2010 |
| Oy Pre-Print Ab | Manufacturing | 1989 |
| Oy Purmo Autic Ab | Financial services | 1989 |
| Oy Rakennuspalvelu Raimax Byggtjänst Ab | Construction | 2007 |
| Oy Rautamo Ab | Wholesale & retail | 1986 |
| Oy Rikta Ab | Manufacturing | 1969 |
| Oy Sand.W Steel Ab | Wholesale & retail | 2015 |
| Oy Sandlin Ab | Wholesale & retail | 1998 |
| Oy Sandlin Invest Ab | Real estate | 2005 |
| Oy Sandsund Steel Ab | Manufacturing | 1993 |
| Oy Sarin Kahvila Ab | Hospitality | 2009 |
| Oy ServicePulse Ab | Professional & scientific | 2024 |
| Oy Silikotek Ab | Wholesale & retail | 1988 |
| Oy Silina Invest Ab | Real estate | 2010 |
| Oy SimplySoft Ab | Professional & scientific | 2021 |
| Oy Sirudent Ab | Health & social care | 2006 |
| Oy Skruw Ab | Financial services | 1986 |
| Oy Smart Invest Ab | Wholesale & retail | 1987 |
| Oy Snellman Ab | Manufacturing | 1956 |
| Oy Sporish Ab | Construction | 1989 |
| Oy Starabooks Ab | Arts & recreation | 2018 |
| Oy Storvest Ab | Professional & scientific | 2012 |
| Oy Sulca Ab | Manufacturing | 2013 |
| Oy T. Björklund Ab | Manufacturing | 1996 |
| Oy TPP-Invest Ab | Real estate | 2003 |
| Oy Tapio Koski Invest Ab | Financial services | 1994 |
| Oy Timberpak Ab | Administrative & support | 1995 |
| Oy Trekomentum Ab | Wholesale & retail | 1994 |