Mercury Records is sort of an anomaly in the recording world. It is an affiliate of the Island-Def Jam recording group (which services just about every genre of mainstream music including pop rock such as the killers, and Rap and hip-hop such as Drake, Ghostface Killah, and Justin Bieber) and yet doesn’t have a single artist as well known in the mainstream as anything on Island or Def Jam.
Mercury records is a stand-alone company operating out of the UK, the artists signed to Mercury don’t really carry over into the same genre as any of the ones signed to Island or Def Jam, erring far more on the side of mainstream radio acceptable music. The music from this label is made to sound like music that is regularly played on the radio, though at least in the US, little actual radio play is received for these tracks or artists.
The Noisettes and Portishead are among the most well known artists that are or were signed to Mercury, and aside from being backed by Island and Def Jam, the actual music has little to do with the music of any artists signed to either of the other record labels. They have the ethos of an independent network though, and despite the radio quality of the artists they sign, they attest that they have little intervention in the final sound of an artist’s album. Despite being backed by a large company, they are not trying to overpower or over market any of the artists that they sign. They want to keep the public happy and their artists happy as well.