TS rejected my SSO short this morning, "Reg SHO. Security not easy to borrow". In other words, they don't want to try borrowing it and probably won't unless you are a large institutional client. TS seems to be among the worst in terms of being able to short the ETF's. Given the chances the markets may decline significantly, shorting the long ETF's is a better strategy. You eliminate the time decay from volatility and reduce counter party risk. I may be looking for another broker which will at least try to borrow the shares to short. I like TS, but this is one big drawback.