BPC has roots and stems in Eve Online. It referees to when an original is copied a limited number of times so that you do not have to pay for the full price of the BPO. In this case a ship BPO can easily be 545,000,000.00 Isk. So i come along, make a few copies and sell it for 10 million at the rate of "5 copies/Run". In this manor you don't pay full price of the BPO and instead of a BPC equivalent to the number of runs you wanted at a percentage of the cost.
In dust 514, everything you buy on the market is considered to come from a BPC, be it from the well known Creodon corporation (NPC COPR that makes tanks, shotguns, etc.) or eventually another player. At this point in time CCP has Seeded (This means made it available at an unlimited quantity) most of the items, however given the history of how CCP does their works in Eve Online; they will be inclined at some point to make it so that only players will eventually manufacture these items, weather it is eve pilots, or dust clones is yet to be known..