Why rise of activist investors is bad for bonds

Bill Ackman appears on CNBC's "Squawk Box" in New York.
Adam Jeffery | CNBC

If 2014 was the year of the activist, then corporate boards had better really watch out for the rest of 2015.

After two record-setting years in a row, activists—think Carl Icahn, Bill Ackman and Dan Loeb—are back at it again only in even bigger numbers this year, according to a report Thursday from Moody's Investors Service.

There have been 54 cases that fall into the category so far, compared with 43 during the same period in 2014. The full-year total for 2014 was 222 cases in nonfinancial companies, a record that just narrowly beat out the 220 notched in 2013.

While the activists themselves defend their moves as taken to improve corporate governance and maximize return to shareholders, authors of the Moody's report say the collective actions too often focus on short-term gain rather than long-term company health.

The results be good for those with equity stakes but bad for bondholders.