For some reason, some of the waves of CP assets that were removed were not marked "rare", while others were. When we see R&D coming in, hopefully someone will go through and fix up the actual rares appropriately.
For now, if nobody has the DC, then it's "rare" (even if there's literally hundreds or thousands of them out there, like the N1).
"May the Grace of Ara go with you, and His Vengeance be wrought upon your enemies."
Only factions can possess datacards. It's commonplace to temporarily join a factions to get datacard access (this is also known as "faction-hopping"). Factions are given datacards by admins, who no longer give datacards to new faction. This forces them to rent datacards from other factions.