Mobile Industry Review, a blog covering the mobile communications industry, is turning subscription only from 27 March.
One company has bought MIR and its entire output exclusively but it is offering corporate subscriptions at £12,000 a year.
MIR has told visitors to its site: "Our new client is unwilling to subsidise our existing audience of readers (300-400k last month) so the content that we'll be creating - reports, video interviews and day-to-day industry news and analysis - will become proprietary from 27th of March. After this date, the public version of MIR will no longer be updated."
Comments on the blog from existing users range from "that price to read a blog? Wow. The economy in the UK must be more messed up than I realised" to "Firstly - congratulations. It's great that you've built such a compelling product that you've been bought. However, this truly is astonishing. Is this the first time a blog has transformed so significantly?"