No, they are (for most vendors, at least the ones that are somewhat reputable and where members of this forum worked with) new old stock or cells that don't fully meet the requirements (not matched, slightly under capacity, etc. - cells that just won't do for vehicles). Once a cell sits in a warehouse for a certain amount of time, they are not considered anymore for things like vehicles. The cells are never used, they just sat around. At some point, there was a surplus of EVE cells that they got rid off through brokers/resellers. Now that it's demonstrated there is a market for that, others jump on the wagon. At least one vendor cells new cells directly from EVE. EVE doesn't like dealing with individual customers, which is why their prices for cells on their web store are so high: these are samples, companies don't care about the price. Once you buy a container full of them, the price drops below what we're paying per cell.