Abstract: We analyze how informed investors can learn from each other through disclosed trades. We show that disclosure always increases market efficiency but its effect on informed investors' profits is ambiguous. When informed investors have highly complementary signals, disclosure makes them coordinate their trades, so their expected profits are higher. Moreover, an informed investor with very imprecise information prefers competition in the presence of disclosure as they learns more from the other informed investors than the market and makes more profits than they would obtain if they is the only informed investors. There could exist herding when information acquisition is endogenous.