Recent strong demand for relatively risky bonds adds to the case that investors are reaching for yield, meaning they are willing to bet more on lower returns in the absence of other options.
Prominent hedge fund firms Och-Ziff Capital Management, Fir Tree Partners, Perry Capital, Paulson & Co., and Brigade Capital Management each bought more than $100 million of new Puerto Rican municipal bonds in March, according to The Wall Street Journal.
The U.S. territory is seen as one of the riskiest municipal bond markets in the world, and its rating was cut to junk status earlier this year. The 21-year bonds originally were sold at a yield of 8.72 percent,which has risen to 8.84 percent according to the report.
Read MoreDespite blockbuster bond sale, Puerto Rico debt-holders still in crosshairs
Greece also raised more than $4 billion on bonds in a Thursday auction. Thanks to strong demand, the five-year bonds were priced to yield 4.95 percent—sharply lower than initial estimates of 5.25 percent to 5.5 percent, according to the Journal.