Alle Firmen mit dem Anfangsbuchstaben I
- Ing. Lorinc Stefan
- Ing. Lothaller Herbert
- Ing. Luchies Jantje Hendrikje
- Ing. Luckabauer Martin
- Ing. Luckabauer Martin
- Ing. Ludwig Herzog e.U.
- Ing. Ludwig Klausbauer Beteiligungs GmbH
- Ing. Luftensteiner Andreas
- Ing. Luger Wolfgang
- Ing. Lugschitz Herbert
- Ing. Luick Forella Michaela Wilhelmine
- Ing. Lukas Neuwirth e.U.
- Ing. Lukic Gabriel
- Ing. Lukschander Kurt
- Ing. Lumbe Markus
- Ing. Lunak Lukas
- Ing. Luntzer Dominik
- Ing. Luppi-Werner Claudia
- Ing. Luschin Wolfgang
- Ing. Lusk Dominic
- Ing. Luttinger Johann Adalbert
- Ing. Lutz Andreas
- Ing. Lutz Florian
- Ing. Löbl Norbert
- Ing. Löffelberger Markus
- Ing. Löffelmann Wolfgang
- Ing. Löffler Gerald
- Ing. Löschenkohl Christian Rudolf
- Ing. Löw Alexander
- Ing. M. ENZI OEG
- Ing. M. Katzbeck GesmbH
- Ing. M. Kronsteiner GmbH
- Ing. M. Michalitsch GmbH
- Ing. MA Brucha-Sereda Jasmin
- Ing. MA Ehrenstrasser Konrad Franz
- Ing. MA Frühwirth Viktoria Barbara Josefine
- Ing. MA Geyer Sebastian
- Ing. MA Klein Markus Stefan
- Ing. MA Linhart Rüdiger Christian
- Ing. MA Mayr Karina Maria
- Ing. MA MSc Reinprecht Markus Karl
- Ing. MA Schaller Andrea
- Ing. MA Sedlaczek David
- Ing. MA Teufl Michael
- Ing. MA Wertek Markus Augustin Josef
- Ing. Macak Daniel
- Ing. Machanec Dalibor
- Ing. Macherhammer Eva Maria
- Ing. Macho Günther
- Ing. Mack Berndt
- Ing. Mack Werner Kurt
- Ing. Mader Erich Gerhard
- Ing. Mader Gerald
- Ing. Mader Herbert
- Ing. Mader Peter
- Ing. Madlener Pascal
- Ing. Madler Michael
- Ing. Mag. (FH) Blaßnig Christian
- Ing. Mag. (FH) Eder Isabella Veronika
- Ing. Mag. (FH) Gratzer Alexander Clemens
- Ing. Mag. (FH) Greiner David
- Ing. Mag. (FH) Guggenberger Hannes
- Ing. Mag. (FH) Hochmuth Christian Markus
- Ing. Mag. (FH) Kaltenbrunner Ingeborg
- Ing. Mag. (FH) Kandler Robert Matthias
- Ing. Mag. (FH) Kopf Johannes Hermann
- Ing. Mag. (FH) Löscher Reinhard Johann
- Ing. Mag. (FH) Manfred Erlbacher, MBA, MA
- Ing. Mag. (FH) Pamperl Ing. Thomas Franz
- Ing. Mag. (FH) Perg Stefan
- Ing. Mag. (FH) Pichler Anton Markus
- Ing. Mag. (FH) Speiser Markus
- Ing. Mag. (FH) Vertacnik Bernhard Klaus
- Ing. Mag. (FH) Wanderer Markus Georg Alexander
- Ing. Mag. (FH) Zajicek Andrea
- Ing. Mag. (FH) Zeilinger Hermann
- Ing. Mag. Achleitner Josef
- Ing. Mag. Andreas Gartner
- Ing. Mag. arch. Maar Christian
- Ing. Mag. arch. Schlager Erich