The first album on Spotify's Miles Davis page is: 30 Masterpieces, from TSK Music (who?). I can't even find an official site for the label, and I don't know why they have the rights to release recordings originally from Prestige. And I don't understand why Spotify let all these unnecessary compilations in, since all official releases and compilations are already on Spotify, with better packaging, remastered sound quality, and reviews from AllMusic right under the tracklist. Ironically this compilation seems to be more popular than many official ones.
Hope Spotify sort this out soon. For those who can't wait, I made an easy-to-browse playlist after Wikipedia's Miles Davis discography.
The first part of the playlist chronicles all the official albums Davis recorded as the band leader, from Blue Period (1951) to Doo-Bop (1992), including the three soundtracks he made. The album Blue Period is not on Spotify, but all tracks are available on The Complete Prestige Recordings 1951-1956, which I put at the beginning of the playlist.
The second part features important live recordings from Columbia Legacy, and the last part consists of compilation and box sets. For box sets devoted to the complete sessions of classic albums like In A Silent Way, I put official album takes from the sessions box sets in the first part, and didn't include them again in the third part.
Here's the Spotify playlist: Miles Davis: Complete Spotify Edition (99 tracks, from 99 albums/box sets). I've tried my best to find the versions that are available on both sides of the pond, still a few albums are missing on Spotify USA. Press Ctrl (CMD)+G to browse in album view, and use the filter bar to find albums more quickly. Also see my previous post for John Coltrane playlists.