Seems as though I have same situation. I recently updated iBooks to 3.2. All was normal for a couple of days, until a red badge appeared, associated with the Store purchases. But I've made no recent iBooks purchase, nor is there any activity or issue with my past purchases.
I investigated, but couldn't determine what the badge referred to, nor how to remove it. I went to Settings, toggled the iBooks "Show Purchases" button on+off; then quit the app; finally reset the iPhone. Badge still appeared.
Oddly, after finishing a book and deleting it from the library, the annoying red badge disappeared. But only temporarily, then it popped back up for no reason.
Must be a bug. Can anybody advise a solution for removing the badge?
Red badge indicates how many updates are available for books you purchased.
I have the same problem on my iphone5. I go to store (from iBooks), touch "PURCHASED" and nothing happen.
On my ipad 2, when I click on PURCHASED in ibook store, I get the list of all books I purchased.
I still can not see from there what books need updating. Since they all have little cloud next to them and no indication if they need updating.
I found (accidentally) that if (in store) you go to "Featured" and in a search box type name of the one of the authors of the book you purchased in a past, you will get list of available books by that author and among those you will see book you purchased with word "downloaded", or little cloud symbol or word "update". As far as I could find it's the only way to see which books have available updates.
Just imagine I had to enter each author name whose books I purchased, scroll thought the list of theirs books, find my books and see if I need to update them ...
I hope Apple will fix both issues:
1. Purchased list when called from iBook store is not getting populated on some devices.
2. Find easier way to show which books need updating.