A bispecific antibody comprising at least two binding domains, wherein a first binding domain binds to a first receptor of the tumor necrosis factor superfamily and a second binding domain binds to a second receptor of the TNF superfamily, wherein the first binding domain binding to CD40 comprises (a) the heavy chain complementarity determining region HCDR1 having the amino acid sequence of SEQ ID NO: 2323, the HCDR2 having the amino acid sequence of SEQ ID NO: 2324 and the HCDR3 having the amino acid sequence of SEQ ID NO: 2325, and the light chain complementarity determining region LCDR1 having the amino acid sequence of SEQ ID NO: 2326, the LCDR2 having the amino acid sequence of SEQ ID NO: 2327 and the LCDR3 having the amino acid sequence of SEQ ID NO: 2328; or (b) the heavy chain variable domain having the amino acid sequence of SEQ ID NO: 2321 and the light chain variable domain having the amino acid sequence of SEQ ID NO: 2322 and wherein the second binding domain binding to 4-1BB comprises (a) the heavy chain complementarity determining region HCDR1 having the amino acid sequence of SEQ ID NO: 2297, the HCDR2 having the amino acid sequence of SEQ ID NO: 2298 and the HCDR3 having the amino acid sequence of SEQ ID NO: 2299, and the light chain complementarity determining region LCDR1 having the amino acid sequence of SEQ ID NO: 2300, the LCDR2 having the amino acid sequence of SEQ ID NO: 2301 and the LCDR3 having the amino acid sequence of SEQ ID NO: 2302; (b) the heavy chain variable domain having the amino acid sequence of SEQ ID NO: 2241 and the light chain variable domain having the amino acid sequence of SEQ ID NO: 2242; (c) the heavy chain complementarity determining region HCDR1 having the amino acid sequence of SEQ ID NO: 2255, the HCDR2 having the amino acid sequence of SEQ ID NO: 2256 and the HCDR3 having the amino acid sequence of SEQ ID NO: 2257, and the light chain complementarity determining region LCDR1 having the amino acid sequence of SEQ ID NO: 2258, the LCDR2 having the amino acid sequence of SEQ ID NO: 2259 and the LCDR3 having the amino acid sequence of SEQ ID NO: 2260; (d) the heavy chain variable domain having the amino acid sequence of SEQ ID NO: 2227 and the light chain variable domain having the amino acid sequence of SEQ ID NO: 2228; (e) the heavy chain complementarity determining region HCDR1 having the amino acid sequence of SEQ ID NO: 2315, the HCDR2 having the amino acid sequence of SEQ ID NO: 2316 and the HCDR3 having the amino acid sequence of SEQ ID NO: 2317, and the light chain complementarity determining region LCDR1 having the amino acid sequence of SEQ ID NO: 2318, the LCDR2 having the amino acid sequence of SEQ ID NO: 2319 and the LCDR3 having the amino acid sequence of SEQ ID NO: 2320; or (f) the heavy chain variable domain having the amino acid sequence of SEQ ID NO: 2247 and the light chain variable domain having the amino acid sequence of SEQ ID NO: 2248. (a) the heavy chain complementarity determining region HCDR1 having the amino acid sequence of SEQ ID NO: 2323, the HCDR2 having the amino acid sequence of SEQ ID NO: 2324 and the HCDR3 having the amino acid sequence of SEQ ID NO: 2325, and the light chain complementarity determining region LCDR1 having the amino acid sequence of SEQ ID NO: 2326, the LCDR2 having the amino acid sequence of SEQ ID NO: 2327 and the LCDR3 having the amino acid sequence of SEQ ID NO: 2328; or (b) the heavy chain variable domain having the amino acid sequence of SEQ ID NO: 2321 and the light chain variable domain having the amino acid sequence of SEQ ID NO: 2322 and wherein (a) the heavy chain complementarity determining region HCDR1 having the amino acid sequence of SEQ ID NO: 2297, the HCDR2 having the amino acid sequence of SEQ ID NO: 2298 and the HCDR3 having the amino acid sequence of SEQ ID NO: 2299, and the light chain complementarity determining region LCDR1 having the amino acid sequence of SEQ ID NO: 2300, the LCDR2 having the amino acid sequence of SEQ ID NO: 2301 and the LCDR3 having the amino acid sequence of SEQ ID NO: 2302; (b) the heavy chain variable domain having the amino acid sequence of SEQ ID NO: 2241 and the light chain variable domain having the amino acid sequence of SEQ ID NO: 2242; (c) the heavy chain complementarity determining region HCDR1 having the amino acid sequence of SEQ ID NO: 2255, the HCDR2 having the amino acid sequence of SEQ ID NO: 2256 and the HCDR3 having the amino acid sequence of SEQ ID NO: 2257, and the light chain complementarity determining region LCDR1 having the amino acid sequence of SEQ ID NO: 2258, the LCDR2 having the amino acid sequence of SEQ ID NO: 2259 and the LCDR3 having the amino acid sequence of SEQ ID NO: 2260; (d) the heavy chain variable domain having the amino acid sequence of SEQ ID NO: 2227 and the light chain variable domain having the amino acid sequence of SEQ ID NO: 2228; (e) the heavy chain complementarity determining region HCDR1 having the amino acid sequence of SEQ ID NO: 2315, the HCDR2 having the amino acid sequence of SEQ ID NO: 2316 and the HCDR3 having the amino acid sequence of SEQ ID NO: 2317, and the light chain complementarity determining region LCDR1 having the amino acid sequence of SEQ ID NO: 2318, the LCDR2 having the amino acid sequence of SEQ ID NO: 2319 and the LCDR3 having the amino acid sequence of SEQ ID NO: 2320; or (f) the heavy chain variable domain having the amino acid sequence of SEQ ID NO: 2247 and the light chain variable domain having the amino acid sequence of SEQ ID NO: 2248.