The band was born in 2003.
Their first recording is a four-tracks-EP titled "Stati Alterati", which is released in December and is positively reviewed by the most important Italian webzines and magazines.
The national radio Radio1 RAI broadcasts the CD, considering Atto IV at the same level of historical Italian prog bands, like PFM and Banco del Mutuo Soccorso.
In 2005 the full-lenght album "A parte" is released with the label Videoradio.
Enthusiastic attentions come from Italy, Germany, Japan, United States, Canada, France; prog-radios, webzines and newspapers broadcast and fully promote the band.
In 2006 they open the Italian dates for Tony Levin, during his World Tour.
In 2008 they had some line-up changes, and ATTO IV are ready for a new chapter.