I think in both cases (Time and DateTime) you will make sure that in the constraint validator you are using the same offset. _OffsetTime.now( offset )_ and  _OffsetTime.now(  )_ will only convert to the same instant, if your default time-zone is the same as the one specified in offset. Take a client server app, where the user specifies a date/time plus timezone and the user is in a different time zone as the server. On the server side the time might get parsed preserving the zone, but then in the constraint validator _OffsetTime.now(  )_ is called using the servers time zone. IMO it is the best to take a potential timezone into consideration. @gunnarmorling, WDYT?