As the voluntary cross-border recognition of eID in Europe (cf. (EU) No. 910/2014, Art. 52 (4)) would already be possible since 29 September 2015, one may think about integrating eID-based registration and authentication for the eIDAS Observatory. As the account holders may well be from non-EU countries, it may be worthwhile to consider the technologies developed for this purpose in pertinent EU-funded research projects such as FutureID (cf. http://futureid.eu) and FutureTrust (cf. https://futuretrust.eu).