Hallmann is a key shareholder and supervisory board member of the international media group Pantaflix AG and its subsidiaries such as Pantaleon Films and Pantaflix Technologies. He also is a key shareholder and supervisory board member of the film production company Filmhouse Germany AG along with its subsidiaries, Summerstorm Entertainment and Egolli Tossel Film. Several movies produced by Filmhouse Germany and its subsidiaries, as well as their contributing actors, have received prestigious awards and nominations. In 2010 Helen Mirren and Christopher Plummer were nominated at the 82nd Academy Awards and the 67th Golden Globe Awards for their performance in the movie "The last station". The movie and its contributors were nominated an additional 15 times and received a total of 3 awards. In 2011 the TV miniseries "Carlos" was nominated 36 times and won 17 awards, amongst others at the 68th Golden Globe Award for "Best Miniseries or Motion Picture Made for Television". In 2014 the movie "Rush" was awarded 6 times and nominated 57 times. One of the major nominations was for the 71st Golden Globe Awards in the category "Best Motion Picture – Drama". In total, the movies that were realized by these three production companies, as well as the contributing actors' performances, were nominated over 210 times and won more than 70 international awards in the past decades.