Is it possible to have a subordinate clause inside a relative clause?

Question

Can one have a subordinate clause inside a relative clause?
What I want to write in English is this:

The economic crisis which started in 2007 resulted in mergers and state intervention, which meant the company became 50% state owned.

My first attempt was this:

Die Wirtschaftskrise, die von 2007 fing an, führte zu Fusionen und staatlicher Eingriff, der bedeutete, dass die Geschäft 50% Staatsbesitz wurde.

However, in the second relative clause the finite verb ought to go to the end of the clause, which would result in:

Die Wirtschaftskrise, die von 2007 fing an, führte zu Fusionen und staatlicher Eingriff, der, dass die Geschäft 50% Staatsbesitz wurde, bedeutete.

That looks wrong to me (with my basic command of German).

Is such a construction correct? Is it allowed but frowned upon by right thinking people? Is there a better way of expressing this?

Answer 1

This construction is not correct. In a relative clause the verb is at the end, but not if the relative clause contains a subordinate clause that depends on the verb.

Your first attempt, with a few other mistakes corrected:

Die Wirtschaftskrise, die 2007 anfing, führte zu Fusionen und staatlichen Eingriffen, die bedeuteten, dass die Firma zu 50% Staatsbesitz wurde.