Bell-Lapuda Model Compartments – Information Security Stack Exchange

I’m trying to figure out Bell-Lapuda model and am having a hard time with compartments.
If Subject 1 is (SECRET, {C}) and they want to read Document 1 which is (UNCLASSIFIED, {A, B, C}), would they be able to? Read down is accepted in the Bell-Lapuda model and subject 1 has permission to read C, but not A or B. So I’m thinking Subject 1 cannot read Document 1 since Document 1 also contains A and B. Is this correct?