The 24-year-old man originally arrested is due to answer bail on 1 July
Six more people have been arrested in connection with a "widely used" source of illegally-downloaded music.
Five men and one woman were questioned in relation to the OiNK website, where pre-released music was distributed, according to Cleveland Police.
Their arrests follow the closure of the website in October as part of an Interpol inquiry.
A 24-year-old man arrested at the time at a flat in Middlesbrough's Grange Road is due to answer bail on 1 July.
The most recent arrests were made on 23 and 28 May, but police have only just released details.
Five men, aged between 19 and 33, and a 28-year-old woman were bailed pending further inquiries.
The arrests follow a two-year investigation by music industry bodies the International Federation of the Phonographic Industry (IFPI) and the British Phonographic Industry (BPI).
Raids were also carried out in Amsterdam in October, where the website's servers were based.