My estimation is that Epic sold all of the IP (name, other trademarks, code, infrastructure, etc) along with the right to be the successor to the extensive license agreements and contracts that they held. Included in this is HR records, which allows the new owner to make offers to the folks that Epic is no longer employing after the deal finishe(d/s).

M&A transactions can get pretty complicated for exactly these reasons; frequently, they disassemble the entire set of assets for sale and divvy them up across one or more buyers, who will pick and choose what they want and then reconstitute whatever they have purchased to their desired degree.