Adding Liquidity - Which Brokers Allow This?

Hi,

I’m trying to make a list of brokers who allow retail clients to add liquidity to their order books. For those who don’t know what I’m talking about, I mean a broker that lets you place a limit order inside of the bid/ask spread and fills you there if another one of their customers sends a market order in the opposite direction (or another limit order that matches/crosses yours). I would search for an “ECN” but that term seems to be completely hijacked in the retail FX world.

Here’s what I got so far:

Interactive Brokers
LMAX
Dukascopy

Anyone know of any others?

theoretically all the white label currenex partners should be able to do this but they come and go so fast I wouldn't touch them with a barge pole. I don't recognise a single name from their list from when I last looked a few years back. The one I was talking too was shady A.F. and went to the wall just months later.
There used to be a few more - hotspot used to have a retail arm for instance, but I think they sold out to fxcm. Those three are the only ones I'd consider unless you can wangle an fxall/ebs account