Big % moves can be misleading. It is most likely a single investor wishing to move on to something else. Possibly maneuvering for EOY tax.
Always look at the transaction value. It is a paltry $57k of shares sold. I don't regard that as 'selling big'. However, if it follows up with big volume tomorrow it may be a traders move and not a single exit.
YBR Price at posting:
52.5¢ Sentiment: Buy Disclosure: Held