Empty public key should be allowed
The public key which consists of zeros was used in the past in mainnet therefore should be treated as a regular key. In C++ is expressed by static const public_key_data empty_pub
.
Block 3682003
with an operation:
{"type":"account_update_operation","value":{"account":"nathan","owner":{"weight_threshold":1,"account_auths":[],"key_auths":[["STM6QRHUtxiEbD1CF4YNNBHyVwTasmTirNArHzXmXyeVvT5E2YFPw",1]]},"memo_key":"STM1111111111111111111111111111111114T1Anm","json_metadata":""}}