From their website (BTW, must be nice to have tax free income!)
Proposal of 70 ct per Share
The dividend will be tax-free once again this year, i.e. without the deduction of capital gains tax or the solidarity surcharge as the dividends are paid out in full from the tax contribution account pursuant to § 27 KStG (Corporation Tax Act) (contributions other than into nominal capital).
Dividends paid to shareholders in Germany are not subject to taxation. Dividends do not involve tax refunds or tax credits.
In the German tax authorities' view, the dividend payment reduces the acquisition costs of the shares for tax purposes.