In terms of volatility positions the Goldman prop desk has been short Treasury vol for who knows how long, but yes there is most likely an offseting position. My guess is they are long swaption vol against the Treasury vol position. As far as what I have seen the past few days Goldman has somewhat covered their short 107 straddle position in the 10yr (buying back mostly Dec straddles, while remaining short a bunch of Nov, probably close to 20,000+). Greenwich has absolutely sold the crap out of the Dec 105, 106, and now today the 104 puts both covered and outright (so some synthetic straddles), about 20,000 each strike, and just relentless every time we downtick. There are definitely large short vol plays not only at the money but also out of the money on the downside in the 10yr options.