How does a forwarder suppose to know all the lower-level co-loaders on the HBL, particularly about overseas shipments?

How does a forwarder suppose to know all the lower-level co-loaders on the HBL, particularly about overseas shipments?

It is important to work closely with the entire trade chain to ensure that the co-loaders submit their documents on time and that the necessary information is shared. The completeness notices, in combination with effective communication between trade chain partners, can assist in these efforts.