I see you are from Germany. Perhaps bankruptcy laws are different there. Under US bankruptcy law the shareholder is last in line to get anything in a bankruptcy. It is virtually unheard of for shareholders to receive anything in a bankruptcy. Exceptions to this generalization are EXTREMELY rare and even those few rare exceptions virtually always involve special circumstances, such as the Texaco bankruptcy. I believe the shareholders survived that one.
The priority for payout in a bankruptcy runs roughly like this. The government gets paid first (taxes). Then wages to workers get paid, including any back wages owed. Then various forms of secured debt, i.e. debt backed by collateral, then unsecured debt. At the very tail end of the priority list come the shareholders. If the creditors don't get paid what they are owed then the shareholders lose ownership of the company. Their shares are cancelled and become worthless. If the company emerges as an operating company it does so under new ownership, usually being owned by the former creditors as partial compensation for not having been paid all the money they were owed.
Almost exactly the same procedure and priorities apply in the U.K.