The company needs to be in debt. However, depending on the owner's personality, they will not agree to a takeover unless they've been in debt for a while. Some will sell as soon as they're in debt while some will drag it on as long as they can. When and if they agree to a takeover, you have three options, pillage, disband and keep them as a child company. Disband does what it says. Pillage you choose what assets you want to keep (workers, titles, events or any tv shows) and the last is where they remain as a child company/developmental territory for you.