From a report by Sihbahn O’Leary in Publishing Perspectives:
BERLIN: Baden-Baden-based market research company Media Control GfK International has launched Germany’s first authoritative e-book bestseller lists, featuring the top 20 fiction titles (“Belletristik”) and the top 10 non-fiction titles (“Sachbuch”).
Der Spiegel will carry the new e-book bestseller lists
According to Börsenblatt new media editor Dr. Michael Roesler-Graichen, Media Control will collect sales data reported by online bookstores and publishers. The reported sales cover about 40 percent of the whole e-book market (B2C) in Germany.
“Media Control does not unveil which stores deliver the data, but is saying that ‘five big e-book retailers’ are the source,” said Roesler-Graichen, adding that since some publishers also deliver sales data, it is likely that they also contain sales made via Amazon.de. And Media Control has plans to collect more detailed data from e-book retailers over time.
More in the article.