Dark pool info dark pool transactions have to be printed within 10 seconds.
dark pools like on-exchange trades are governed by Reg NMS, which prohibits trade throughs, which basically means you have to satisfy the best lit top of book. So for a 100k share order in the dark pool, let's say Arca has the best price for 1000 shares, you'd have to do 1000 share on Arca to avoid trading through the market, which would print that to the tape, then 99k shares in your dark pool.