Publishing an acquired app under its "original" name/id?

Hello everyone,

I'd like to discuss a question that came up in my mind and that I couldn't find an answer on the inet.

Let's say company B has published a good running iOS app, that company A acquires from B. Company A is interested in keeping the app in the app store under its original name. Only the "Seller" name should be updated from 'Comp. B' to its new owner 'Comp. A'. Can company A resign the app with its own developer certificate and distribute it in the appstore? Will users, who already have purchased the app from company B, get future updates for free or will they have to repurchase the app again? The later will mean that company A will loose the current user base!

Any ideas on this matter?

Thanks, Resa