There are a few sites out there, mint.com, swipely.com, blippy.com, that have total access to your banking and credit information. You need to give them your userid and password. Once they have that, they are able to access all of your purchase history.
My question: How is this done? Is this a service being provided by the banks? Are they simply logging into your banks web site and scrubbing the pages? Is there a company that provides these tools or does each of these sites write the code in house?
If anyone has some knowledge they are willing to share, it would be greatly appreciated.
I think it may have changed since the takeover by Intuit, but certainly before that Mint used Yodlee to obtain this information.
As I understand it, Yodlee uses OFX for communicating with financial institutions, but also does some screen scraping.
See here for further info.