I dont think anyone has that data. Individual companies dont have a record of who owns their stock and what they bought it at. Even individual owners sometimes dont know their own cost basis, let alone their broker or some centralized authority. This is further complicated by the fact that >50% of trades now occur outside of exchanges [1]You might be able to estimate a similar attribute by looking at IPO history and additional primary offerings, but that also has major challenges. It doesn't inc...