Last week, we saw a substantial amount of options activity in the iShares iBoxx $ High-Yield Bond ETF (HYG), says Jay Soloff of Investors Alley.

HYG is a very popular ETF used for tracking junk bonds (aka high-yield bonds). The ETF normally has about 220,000 options contacts that trade per day on average, but on a busy day last week it traded over 600,000 contracts. On that day, 97% of the action was in puts. Normally that would be considered bearish, but it looks like most of the large put block trades were done as hedges rather than for speculative purposes.

Learn more about Jay Soloff at Investors Alley.