Ok, that's clear enough. So you have a list of IP addresses, and you want to block them on your FWs.
You can use the notion of a dynamic object, explained here: https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solut...
Dynamic object is basically an empty logical box that can be used in the rules and should be filled with IP addresses on the GW side. Mind, you will need to script the population of the dynamic object in use with GW side scripting.
Another option is to use MGMT API and fill in a certain group on the management side, but every time the list is changed, you will have to re-push policy on GWs.