You are saying your client had to pay Germany income tax with no income? Glade I don't live there

Form 1116 is for foreign taxes paid or accrued. If -0-, we don't use this form. If paid or accrued then we report both the taxes paid and the foreign based income.

Client shows a loss from the farm AFTER claiming the depreciation.

Germany taxed the income before any depreciation was claimed.

Do I input the negative number on Form 1116?

If there was a loss, are you sure this is a creditable income tax and not another kind of tax?

Clearing that hurdle - isn't there a way to link the rental property to the 1116? There won't be a credit since no double taxation but you would get the benefit of the carryback/carryover.

Just saw your post re the farm. 1116 wants gross foreign income and then deductions directly attributable to that income.