This article is a good read about what has happened before after the hack and as well as where the recovered bitcoins must go.
Article:
Who gets the $3.6BN in Bitcoin US seized in Bitfinex hack?It's actually a developing story and we still need to wait further for the decision about it. It is not only bitfinex that will decide on this, do they or not?
Seems like a lot of others want their Bitcoin back, but considering that Bitfinex compensated them somehow, just that it seems like the compensation was valued at what it was when the exchange was hacked? So it's like the amount to be returned to the original owners were the value of their assets way back then in USD, instead of the exact assets themselves. It's kinda difficult ig, but as I said, considering how Bitfinex compensated the owners, it wouldn't be odd for them to say that they technically own the Bitcoin now, and not the users.