According to Edith Reiter's 2014 book this instrument was completed on 1 December 1996 and originally sold to a buyer in Finland.
Howe & Hurd (2004) describe heckelphone #5003 as a model 36 voll cons.
As of 2004, heckelphone #5003 was reported to be located in Helsinki, Finland, owned by the Finnish National Opera, who likely acquired it directly from Heckel. It has been played prominently by oboist Tapani Salonen in the 1999 premiere of Patrick Vidjeskog's Sonata in modo classico for for heckelphone and piano.