Many songs are created by multiple artists. This could be a main artist with one or more featured artists or an equal collaboration of different artists. As far as I know, these scrobbles are either counted only for the collaboration (which is treated as a completely new artist) or only for the first artist in the list. For the sake of proper stats, the scrobbles should be counted for each participant separately. This requires the recognition of artist names and standard join phrases like "&", "feat.", "versus" or "/" (and their counterparts in different languages). The effective result of scrobbling "Artist 1 & Artist 2 - Title" would be logically 1 scrobbled song in the history and 1 scrobble for each of the participating artists. Exceptions: A singing duo or when the join phrase is part of the band name, it wouldn't make much sense to separate. These informations can be obtained from music databases.