"Ownership" is not the word to be using.
The 205.238.192/18 is ALLOCATED to Epix. Meaning: the are authorized
to use the addresses or to assign them to someone else to use.
The /24 is probably ASSIGNED to you. Meaning: you can be an end
user of the addresses.
The /18 is not registered with ARIN as non-portable, so the
portability call is exclusively up to the administrator of that
block.