Are activist investors hurting the US economy?

Activist investors hurting U.S. economy?

Activist investors are hurting the economy by forcing companies to return capital to shareholders rather than undertake new projects, contends Larry McDonald, Societe General's head of U.S. strategy.

Over the past 18 months, corporate capital expenditures have fallen while buybacks have risen, which "just tells me that we're in a market where activists are very bold. They are exerting their power and in many cases, more influence than in recent years," McDonald said.

In the most famous recent example of the trend, Carl Icahn's calls for increased buybacks at Apple have been largely met by the company (whether as a direct result of Icahn's influence or not) and in April, Apple increased its two-year capital return program to $200 billion.

The consequent impact on the economy is very real, says McDonald.

"Without capex growing and expanding, you're talking thousands and thousands of jobs that aren't being created because companies are just financial engineering their own balance sheets," he said Wednesday in a "Trading Nation" interview.

However, Erin Gibbs of S&P Capital IQ says that if activist investors are having an influence, they are "actually making CEOs act rationally for the best interests of the company."

"It is more frequently much more difficult to find valuable capex investments when facing slower growth in a mature business environment. Certainly there are extreme cases, but overall I view the share buybacks over capex as a rational investment choice for many of the S&P 500 companies," Gibbs said, adding pointedly: "If one feels we should become more of socialist state, and cash should be invested for the greater good of the American economy rather than for the benefit of the company shareholders then I could see an argument for opting for less valuable investment."

Additionally, Gibbs questions how much companies have actually stepped back from capex. As a percentage of revenues, capital expenditures have risen 6.8 percent year over year as of the first quarter, she reports.

Read More Moody's to CEOs: Think twice before buying back stock

Of course, companies' revenue also fell in the first quarter. This, plus Gibbs' trailing-12-month comparison, explains the difference between Gibbs' and McDonald's assessments of capital expenditure levels.