I think the only good case is with KSI, but that's not actually a blockchain even if they use the name in marketing. In their case, they limit themselves to ve

I think the only good case is with KSI, but that's not actually a blockchain even if they use the name in marketing. In their case, they limit themselves to verifiable timestamped witness. Someone can still submit bad data, but now you have a log that at time T entity E submitted document D, and if it turns out to be fraudulent you can't backdate or put a different one for it (could be also used to detect tampering with sensors if you receive something that shouldn't pass a sensor that worked correctly yet you obviously have it)