That's one of the things I love about this forum....instead of the typical 'I'm right you're wrong' stuff you see on so many other boards....the discussion here often leads me to research things that increase my knowledge base. This question of auction markets versus MM specialist markets is a case in point......
What I've found out is the difference between a true auction market and a MM specialist market.
A true aution market involves MMs simply placing or accepting orders from buyers and sellers....not accumulating positions or going short, basically just acting as clearing houses.
A specialist market deals more with thinly traded issues on smaller electronic exchanges like the Naz. To provide liquidity MMs will quote both a buy and ask, even if they don't have clients looking to buy or sell.
And in the case of the TSX....from what I've read its a hybrid. For issues with lots of volume and liquidty MMs act as a clearing house and stocks with lots of trading....its an auction market. But with thinly traded issues, and I have to assume RVX would fit that bill....then they serve as specialists, providing liquidity even though there may be a dearth of either buyers or sellers...or both.