Ownership relates to the actual owner of the legal rights associated with a patent.
Patent owners can change via assignments; however, authentic inventors cannot change.
In the case of an independent inventor (i.e. absent any contrary agreement or duty to assign a patent), the inventor and the owner are usually the same person.
At the time a patent application is filed with the USPTO, the actual inventor or co-inventors may be required by their employer to assign their interests in such inventions to their employer or perhaps to their employer’s applicable government or commercial customer, pursuant to any applicable contract.
Often, especially in a corporate or a university setting, the inventor does not own the patent; the corporation or university does.