This is a space of vector valued Siegel modular forms with real representation $\mathrm{Det}^{ 13}\otimes\mathrm{Sym}^{ 12 }$. The following table gives the dimensions of various subspaces of $M_{13, 12}(\mathrm{Sp}(4, \mathbb{Z}))$.
| Total | 5 |
| Non cusp | 0 |
| Cusp | 5 |