In response, EMI issued a statement that offered no greater clarity but hinted at a negotiation: “Danger Mouse is a brilliant, talented artist for whom we have enormous respect. We continue to make every effort to resolve this situation and we are talking to Brian directly. Meanwhile, we need to reserve our rights.”

In most cases this turn of events would signify defeat: an artist battles a record label, and his music vanishes down the memory hole. But in the peculiar way that Danger Mouse has built his career, “Dark Night of the Soul” seemed to be an oblique victory, in which failure at official business can generate notoriety and, ultimately, lead to success in other endeavors.

For fans the sticker’s winking reference to illegal downloading  “Dark Night of the Soul,” like most albums in the age of leaks, is widely if unofficially available free online  was amusingly familiar. Five years ago Danger Mouse released “The Grey Album,” a mash-up that used unauthorized Beatles and Jay-Z samples and became a bootleg Internet phenomenon. The once-obscure Danger Mouse was instantly catapulted to fame, getting high-profile gigs producing Gorillaz and others; Gnarls Barkley, his group with the singer Cee-Lo Green, scored a No. 1 hit around the world with “Crazy.”

“From ‘The Grey Album’ on, he has proven himself a master of improvisation,” said Jeff Chang, author of the hip-hop history “Can’t Stop Won’t Stop.” “He’s really interesting tactically, in terms of trying to figure out how to position himself and still come out ahead.”

In a telephone interview Danger Mouse said that he and Sparklehorse (whose name is Mark Linkous) had worked on “Dark Night of the Soul” for two years, with a plan to maximize creative input from everyone involved: they gave instrumental tracks to singers they liked  among them Iggy Pop, Suzanne Vega and Julian Casablancas of the Strokes  and asked them to add vocal parts however they saw fit.