Without a lease agreement, easement, or permission, as the property owner you generally have a removal claim against the TEN. However, the network operator can initiate an expropriation procedure when asserting the removal claim, so the situation can also backfire.
- The TEN (or their predecessors) apparently failed to secure the line during the reunification (this was not necessary in the GDR)
- Your municipality/city or the TEN or their predecessors have apparently failed to register the respective easements during the land register adjustment procedure.
- The previous owner(s) neglected to demand/register the respective easements when selling the property
- At the moment, as the property owner, you are the one holding the black mark. The fact that you had digging done without a line inquiry does not make things easier; however, you can hold your contractor responsible here, since they also have a duty to investigate and may not rely solely on your oral statements.
Get back in touch with the TEN. Refer to the missing securing of the line (and not necessarily to your removal claim). Maybe you can agree on a cost sharing; you already have a contractor on site. But in principle, relocation costs are to be borne by the party causing them (you). However, you might have a claim against the previous owner, which would probably be difficult to enforce.
What does the purchase contract look like? Are lines mentioned on the property here?