what exactly is EDGEA and how is it that it can pay you to remove liquidity? doesn't make much sense...
There is a footnote to that... The removal rate on EDGA is contingent on the attributed MPID adding (including hidden) and/or routing a minimum average daily share volume, measured monthly, of 50,000* shares on EDGA. Any attributed MPID not meeting the aforementioned minimum will be charged $0.0030 per share for removing liquidity from EDGA (0.20% of dollar value for stocks priced <$1.00). *For the month of July 2010 only, 50,000 average daily volume threshold will be multiplied by a fraction, the numerator of which shall be the sum of the daily consolidated volumes for each ECN-traded symbol for all days that such symbol is traded on the ECN during the month of July and the denominator of which shall be the monthly consolidated volume for all ECN-traded symbols during the month of July. http://www.directedge.com/SubscriberInfo/FeeSchedule.aspx
they charge to add and pay to take... but very small amount, 2 cents per 100 shares. It's almost like a free ecn, except with a very small inverted structure.