I have to respond...

In example #4 there is no facilitation between buyer and seller. The buyer buys from one party (1 trade) and the buyer then sells to another party (2nd trade). These are two separate and distinct transactions comprising 2 trades with a total of 200 hundred shares.

That is the way Nasdaq sees it and calls it.

4) A Market Maker receives an order to buy 100 shares from it's client. It does not have 100 shares in its inventory. It must go buy 100 shares from someone else. It then sells these 100 shares to the client. Thus, there are two trades in this example for a total of 200 shares.

Read more: http://www.nasdaq.com/investing/glossary/v/volume-counting#ixzz3aF1Mjdnq