Field help: (2019) Loss carryforward from capital assets with final withholding tax (sect. 20 para. 6 sentence 5 of the Income Tax Act (EStG))

If the negative income is not offset or not fully offset in the previous year, you will receive an assessment notice on the "remaining loss carry forward" (verbleibenden Verlustvortrag).

Losses that have not been offset are carried one year back and offset against the positive profits of the previous year. If a loss persists after the carryback, the loss will be carried forward to the next year by your tax office. You can limit the amount of the loss carryback if you expect only a small or no tax effect of the loss deduction in the previous year.