Alle Firmen mit dem Anfangsbuchstaben I
- Ing. Hießl Alena
- Ing. Hilbrand Fabian Alois
- Ing. Hillinger Wilhelm
- Ing. Hingerl Werner
- Ing. Hinterbuchinger Hannes
- Ing. Hinteregger Bernd
- Ing. Hinterramskogler Johann
- Ing. Hinterseer Andreas
- Ing. Hintersteiner Dietmar
- Ing. Hipfel Stefan
- Ing. Hirsch Andreas
- Ing. Hirsch Gerald
- Ing. Hirschhofer Ulrich Andreas
- Ing. Hirt Carmen Barbara
- Ing. Hirzinger Martin
- Ing. Hitthaler Konrad
- Ing. Hlous Thomas
- Ing. Hnat Andreas Rene
- Ing. Hobel Christian
- Ing. Hochbichler Karl
- Ing. Hochegger Rene
- Ing. Hochhauser Bau- u. Sanierungs- technik GmbH
- Ing. Hochreiner Peter
- Ing. Hochsteiner Klaus
- Ing. Hochstrasser Christoph
- Ing. Hochstöger Johann
- Ing. Hochstöger Rudolf
- Ing. Hochwarter Wolfgang
- Ing. Hofbauer Josef
- Ing. Hofbauer Wilhelm
- Ing. Hofegger GmbH
- Ing. Hofeneder Heinrich
- Ing. Hofer Erich Franz
- Ing. Hofer Gerald Roman
- Ing. Hofer Gerhard
- Ing. Hofer Stefan
- Ing. Hofer Wolfgang
- Ing. Hoffmann Günther
- Ing. Hofinger Anna
- Ing. Hofinger Markus
- Ing. Hofmaninger Gerald
- Ing. Hofmann Georg
- Ing. Hofmann Hubert
- Ing. Hofmeister Christoph Robert
- Ing. Hofstädter Marianne Karin
- Ing. Hofstätter Helmut
- Ing. Hohenegg Stefan Karl
- Ing. Hohensinner Heribert
- Ing. Hohl Viktor
- Ing. Holcapek Wilhelm
- Ing. Hollan Ivan
- Ing. Hollergschwandtner Johann Georg
- Ing. Holzer Franz
- Ing. Holzer Michael
- Ing. Holzer Sarah-Sophie
- Ing. Holzer Walter
- Ing. Holzhacker Michael Kurt
- Ing. Holzhammer Peter
- Ing. Holzmann Norbert
- Ing. Honisch OEG
- Ing. Hopfer Andreas Karl
- Ing. Hopfner Patrick
- Ing. Hora Petra
- Ing. Horcicka Gerhard Otto
- Ing. Hornaus Thomas
- Ing. Horner Bernhard Peter
- Ing. Horner Christian Helmut
- Ing. Horsetzky-Hornthal Paul Ernst
- Ing. Horvat Ernst
- Ing. Horvath Gregor
- Ing. Horvath Jochen Alexander
- Ing. Hoschek Peter
- Ing. Hoschka Leo
- Ing. Hotter Christian
- Ing. Hrabalek Ernst
- Ing. Hradecky Christian
- Ing. Hrdina Bernhard Franz
- Ing. Hrdy Helmut
- Ing. Hristova Ani
- Ing. Huber Alfred