What purpose does this broken plastic clip serve in the MacBook Pro? Yesterday I opened my mid 2010 15" i7 MBP (model 6,2) in order to replace its HDD. Everything went perfectly fine. Except that I noticed a broken little piece of plastic a little above the battery, which is fixed by two screws, which I have no idea on what purpose it had. 



In the end, I just wanted to know what is that piece's purpose, if I should be worried that it is slightly broken, if I can replace it somehow.
That clip holds the bottom piece snug in the middle. I would remove the broken plastic to avoid bending the metal tab that matches this on the bottom case. Also, you don't want it pushing on the connectors that are delicate and behind the metal cage above it. Lastly, if the piece breaks free it could wedge in the wrong spot (like a blower or worse) and cause more harm than it should.

You can see about a repair part from Apple by contacting AppleCare and this sort of thing is often sold used when a machine is liquid damaged or otherwise scrapped for parts. Many places sell used parts like ebay, amazon and ifixit.