From their site: Welcome to the Internet UPC Database. This free service is run as a hobby of mine. This site isn't limited to UPCs any more. First of all, the term 'UPC' has been deprecated the new term is UCC-12. But the world has moved beyond that. As of January 2005, retailers in the U.S. are supposed to be able to support the EAN/UCC-13 code (the rest of the world has done this for years), which uses similar symbology, and one additional digit.
The following is a list of historical changes that were made to this asset. Typically, once an API is published on ProgrammableWeb.com, the data we keep about that asset gets updated over the course of its life. For example, the endpoint or home page of the documentation might change. As a means of enforcing the integrity of our data, every time a non-trivial change is made to the data we keep about an asset, we require the entry of some changelog text before that change can be saved. This way, we have a great audit trail of all activity surrounding the asset. For each asset, the changelogs begins with the moment an asset is approved for publication on ProgrammableWeb. If you spot an error in our data and believe that a record needs to be updated in some way, the ProgrammableWeb team would very much like to hear from you at firstname.lastname@example.org
So far, we don't have a record of any changes to this API