The cosy thought that the Kindle stops other people see what you're reading on the tube has seen sales of embarrassing novels soar, but don't get too comfortable: the device actually makes it much easier for certain people to peek over your shoulder.

A report by Cindy Cohn of the Electronic Frontier Foundation finds that although libraries protects your reading habits fairly sturdily, no such protection exists for e-books. Google, Amazon and Barnes and Noble can all share customer information with law enforcement agencies and civil litigants. Amazon, Barnes and Noble, Knobo, Sony, OverDrive and IndieBound can all share customer information without their consent.  Governments don't need warrants to ask Google and Amazon for information about what individuals have been reading: and historically, they do ask.

We know this because libraries have been pretty fierce at batting back these kinds of requests. Back in 1987, Mother Jones writes, the FBI asked a Columbia University librarian to "keep an eye out for commies". She didn't like the request, and set up a "library awareness" program - first bringing the issue to public notice.

Then, in 1998, independent counsel Kenneth Starr tried to get hold of Monica Lewinsky's reading history during the time she was involved with Bill Clinton. The US District Court in Washington drew up the first set of standards for when this information can be released.

Since then, similar cases -  police trying to get libraries to disclose who has been taking out books on drugs, or Osama Bin Laden, or campaign financing, have been mostly settled in favour of reader's privacy, putting customer's rights in a fairly safe position.

But this has not been translated into a workable law for digital records  -  which remains in its infancy. Here's Mother Jones:

Cohn says that many Americans remain in the dark about how much of their private e-information is a veritable open book to the government: "It's going to take a few more Petraeuses before people understand what the world of ubiquitous surveillance means for them."