One aspect of the question regarding a possible relationship between blockchains and Open Badges is to wonder whether the blockchain should be treated as some kind of add-on to the existing Open Badge structure/standard, or should Open Badges be integrated within a blockchain?
A starting point for an informed answer to this question is to do a simple test: take an Open Badge generated by one issuing platform and try to import it into another issuing/hosting platform. I have done this experiment recently, taking only a very small sample, and the results were rather… (un)conclusive — BTW, one suggestion for the Standards Working group would be to run a real life interoperability test (not just through a formal proof) across all platforms and publish the results.
Interoperability is a classical problem to which the ePortfolio community was confronted some years ago and to which no convincing answer was ever provided — the IMS-Global ePortfolio and Leap2A specifications (2 specifications for interoperability is already one too many!!!) are only used by a handful of ePortfolio platforms — notwithstanding that there are many ePortfolios that do not use any ePortfolio platform at all! Moreover, when we organised plugfests during previous ePIC conferences, we had to admit that 3 platforms using the same technical specification (IMS ePortfolio at the time) had problems understanding each other: exporting one ePortfolio from one platform then importing it to another did not always work properly…
One could have imagined that with a structure much simpler than ePortfolios, the problem of interoperability would have disappeared. It has not. And now that we have allowed extensions to the specification, the order of magnitude for potential interoperability problems has increased geometrically, not just arithmetically. Yet, the possibility to extend the specification, even by one single issuing platform, willing to gain a competitive advantage, with a better or innovative service, should probably be allowed. We certainly do not want a “one-size-fits-all” issuing platform. Innovation must go on!