Sources: European Commission, AGA - Annotated Model Grant Agreement, Annex 5 HE, Open Science-Website of the ERC
The guidelines for making results from DFG-funded research available do not include an obligation, but a call for publication in open access:
Sources: Open Access sites of the DFG, DFG-Vordruck 2.00 - 1/21, page 33
The BMBF has included Open Access as a standard in its project funding. The Open Access Strategy contains the following requirements:
Sources: BMBF-Strategie, page 8, Open Access-Initiatives of the BMBF