completeness of complexes

[OliviaViessmann]

Hi,

I have a question about the completeness of the complexes in DIPS-Plus.
I find many complexes in DIPS-Plus that do not have a complete set of pairs for the entire complex.
For example 1dnu (https://www.rcsb.org/3d-sequence/1dnu): This is a 4-chain complex with chains A,B,C and D. But DIPS-Plus only contains binary pairs D,B and A,B. But C is contained in no pair.
Why is that? Is there a way to construct all sets of binary pairs? Or at least a set of pairs that in union contains all chains?

Thanks
Olivia