| Active Invest Oy | Construction | 2009 |
| Agriina Oy | Agriculture & fishing | 2021 |
| Agripiha Avoin yhtiö | Agriculture & fishing | 2010 |
| Ala-Sakari Oy | Agriculture & fishing | 2024 |
| Alakorven Tila Oy | Agriculture & fishing | 2019 |
| Ateljé Kielo Oy | Hospitality | 2021 |
| Avoin yhtiö Luontaispiste Kolmiapila | | 1989 |
| CHH Express Oy | Transport & logistics | 2025 |
| Cuenta Oy | Professional & scientific | 2013 |
| DEFCOM Oy | Real estate | 1992 |
| Eläinkaverit Voima ja Valo Oy | Health & social care | 2022 |
| Green Recycle Oy | Manufacturing | 2020 |
| Heino Vanhala Oy | Financial services | 2014 |
| Hellpuri Oy | Mining & quarrying | 1998 |
| HighCap Oy | Professional & scientific | 2018 |
| Hukkatyö Oy | Other services | 2014 |
| J&V Vuokrayhtiö Oy | Real estate | 2020 |
| J. Heiskari Oy | Wholesale & retail | 1989 |
| JMC Engine Oy | Manufacturing | 1997 |
| JMC Partners Oy | Manufacturing | 2026 |
| JMC Solutions Oy | Manufacturing | 2016 |
| Kauppahuone M Mikkonen Oy | Wholesale & retail | 1998 |
| Kiinteistö Oy Askola | Real estate | 1980 |
| Kiinteistö Oy Kvantti | Real estate | 1986 |
| Kiinteistö Oy Pekanraitti | Real estate | 2016 |
| Kiinteistö Oy Ruukin Metsätalo | Real estate | 1990 |
| Kiinteistö Oy Ruukin Verstas | Real estate | 1991 |
| Kiinteistö Oy Ruukintori | Real estate | 1981 |
| Koneurakointi H&i Kuoppala Oy | Construction | 2020 |
| Korpitaito Oy | Professional & scientific | 2024 |
| Kourmu Oy | Agriculture & fishing | 2023 |
| Kuljetus T. Niinimaa Oy | Transport & logistics | 2014 |
| Kuusisalo Oy | Construction | 1996 |
| Lehto Invest Oy | Administrative & support | 2006 |
| Leipomo Savilaakso Oy | Wholesale & retail | 2020 |
| Lentävä Kurki Oy | Wholesale & retail | 2021 |
| Loisto Building System Oy | Construction | 2023 |
| Luomulehto Oy | Administrative & support | 2002 |
| M. Niinimaa OY | Manufacturing | 2021 |
| Marsaco Oy | Wholesale & retail | 2005 |
| Merita Pizza Ruukki avoin yhtiö | Hospitality | 2017 |
| Metsätoimisto Kiramo Oy | Agriculture & fishing | 2014 |
| Naturak Oy | Real estate | 2016 |
| Naturcom Oy | Wholesale & retail | 1994 |
| Nerona Oy | Wholesale & retail | 2006 |
| Nuttuskehveli Oy | Arts & recreation | 2007 |
| Nättisen kuljetus Oy | Transport & logistics | 1993 |
| Ossi Pitkänen Ky | Manufacturing | 1985 |
| Osuuskunta Yrttiaika | Wholesale & retail | 2014 |
| Oy Hot Igloo Ab | Professional & scientific | 2003 |
| PM LaserClean Oy | Administrative & support | 2024 |
| PT Vision Oy | Mining & quarrying | 2017 |
| Paavolan LVI-Tekniikka Oy | Professional & scientific | 2007 |
| Paavolan Vesi Oy | Water & waste | 1965 |
| Palokankaan Tila Oy | Agriculture & fishing | 2024 |
| Parki Oy | Real estate | 2024 |
| Pehkolan Mallastamo Oy | Manufacturing | 2017 |
| Perhepalvelu MinttuMaria Oy | Other services | 2021 |
| Plantanova Oy | Wholesale & retail | 1991 |
| Pohjolan Arvotalot Oy | Real estate | 2008 |
| Ponionni Oy | Wholesale & retail | 2020 |
| Puusepänliike A. Punkeri Ky | Construction | 2013 |
| RPM Karting OY | Arts & recreation | 2025 |
| Raahen AK-kiinteistöt Oy | Real estate | 2014 |
| Rauta-Maatalous Jaatinen Oy | Wholesale & retail | 1983 |
| Ruukin Matinet Oy | Wholesale & retail | 1996 |
| Ruukin Saha ja Höyläämö Ky | Manufacturing | 1996 |
| Ruukin Villa Oy | Real estate | 1992 |
| Ruukin Yrityspuisto Oy | Real estate | 1993 |
| SCG Specialist Contractors' Group Oy | Construction | 2015 |
| SEA Recycling Oy | Manufacturing | 2023 |
| SX Collective Oy | Wholesale & retail | 2026 |
| Sanala Oy | Real estate | 2011 |
| Saston Puutuote Oy | Agriculture & fishing | 2009 |
| Saunasi Oy | Construction | 2024 |
| Siikajoen Solina Osk | Health & social care | 2021 |
| Solupak Insulation Oy | Manufacturing | 1985 |
| Suomen Kalustetehdas Oy | Manufacturing | 2022 |
| Suomen Varaosakeskus Oy | Wholesale & retail | 2012 |
| SydänmaanKoti Oy | Health & social care | 2009 |
| TeknoComp Oy | Manufacturing | 2007 |
| Telso Oy | Manufacturing | 2020 |
| Tervatehdas oy | Hospitality | 2024 |
| Tietoruukki Kommandiittiyhtiö | Information & communication | 1987 |
| Toivo Orava Ky | Hospitality | 1980 |
| Trade-Matik Ky | Wholesale & retail | 1992 |
| Turva Service Oy | Administrative & support | 2022 |
| U2 Online Oy | Professional & scientific | 2019 |
| Vaiscom Oy | Manufacturing | 2012 |
| VeKaKone Oy | Construction | 2021 |
| Veli-Matti Jaakola Oy | Financial services | 2011 |
| Viazi Oy | Information & communication | 2023 |
| Viljasin Oy | Construction | 2006 |
| Viljolan Tila Oy | Agriculture & fishing | 2024 |
| Vähäkankaan Tila Oy | Agriculture & fishing | 2020 |