It’s a shame that the other answer got half of it right, but unfortunately only the “back half".

These really are “add-backs”, see e.g.

http://www.kpmg.com/DE/de/Documents/german-tax-monthly-novem...

http://www.luther-lawfirm.com/uploads/tx_fwluther/German_Tax...

http://www.bakermckenzie.com/files/Uploads/Documents/Germany...

And this is the text from my own slide on add-backs from a tax translation seminar I ran last year at a large German law firm:

Hinzurechnungen – add-backs (examples):

Entgelte für Schulden – cost of debt
Defined as interest expenses, discounts on loans, and cash discounts granted not attributable to ordinary business activities.
Prior to 2008, this add-back was called Dauerschuldzinsen (interest on long-term debt, and was defined as 50% of interest on debt incurred to establish, expand, or enhance a business.

Gewinnanteile des stillen Gesellschafters – profit shares of silent partner
Miet-und Pachtaufwendungen für bewegliche/unbewegliche Wirtschaftsgüter des AV, die im Eigentum eines anderen stehen – rental and lease expenses for moveable/immoveable fixed assets owned by third parties:
- 20% of moveable assets, 50% of immoveable assets
- Erbbauzinsen are classified as lease expenses on immoveable assets.

Aufwendungen für zeitlich befristete Überlassung von Rechten
Rechte defined as e.g. Konzessionen, gewerbliche Schutzrechte, Urheberrechte and Namensrechte, but not licences that entitle the holder to transfer derivative third-party rights.