although they didn’t have any shares of FB available for me to short on the day it started trading (may 18th) they did have some SOCL (social media etf) come available shortly after FB started trading, which i took advantage of (i first posted they were not available right after FB started trading and then posted that they were available once again shortly thereafter).  this etf doesn’t have a lot of trading history to chart and i’m watching it closely here as it approaches what little support that can be inferred from its relatively brief chart history.  i would not advise entering a short of SOCL here as it is very extended in the short-term and could put in a bounce soon.  however, a move below that lower line, especially after some type of bounce or consolidation to help alleviate the near-term oversold conditions, might provide and objective short entry.