This directory aims at historical review only and does not claim to provide actual information.
| Company Name | Address | Postcode | Place | Awarded on | Type of award |
| Dr.techn. Ernst Linsinger & Co Gesellschaft m.b.H. | Dr. Linsinger Straße 23-24 | 4662 | Steyrermühl | 16.09.1983 | revocable |
| DONAUSÄGE Rumplmayr GmbH | Bahnhofstraße 50 | 4813 | Altmünster | 20.11.1980 | revocable |
| Donau Touristik GmbH | Lederer Gasse 10 | 4015 | Linz | 17.12.2002 | revocable |
| Dipl.Ing. Günther GesmbH & Co KG | Hamerlingstraße 13-15 | 4020 | Linz | 08.05.1990 | revocable |
| Dipl.Ing. Emil Bertalanffy KG | | 4866 | Unterach am Attersee | 13.05.1975 | revocable |
| DIAMOR Karl Rieker GesmbH | Aderstraße 33 | 4850 | Timelkam | 07.01.1985 | revocable |
| DIAMANT-Nahrungsmittel GesmbH & Co KG | Maria-Theresia-Str. 41 | 4600 | Wels | 25.11.1991 | revocable |
| Company Name | Address | Postcode | Place | Awarded on | Type of award |
