It's market madness!

The market closed in the green, starting this week off on a good foot.

Twitter Inc. (TWTR) didn't get the memo though. The social media company slumped after it was reported that it was clearing out bots. The company removed over 70 million accounts in June and May. 

However, investors may not have to worry too much. Executives at Twitter say that the clean out shouldn't hurt the number of active users per month.

Biotech is in a buying mood. TheStreet intern Alexander Nicoll is reporting that Biotech is on track to hit a record number of M&A's.

That's it for Monday. Stick with TheStreet for more updates.