The most up-to-date owner information we have is available from the 'owners' component of a property record.
This data comes to us in a combined format, without person names being parsed out into first, middle, last, etc. components. These combined names are in a partially standardized format, but parsing this with complete accuracy is tricky; see the above point.
If having parsed person names is more important than freshness, our latest deed buyer first and last name fields can be used to obtain names in a partially parsed format. There is some freshness lost here because sometimes our owner information is more up-to-date than our deed records. Also, note that there is still trickiness around separating person from non-person names, e.g. there are cases with a buyer first name of a person's name and a buyer last name of "TRUST".