When it comes to market investing, ESG stocks are difficult to define and benchmark, said Witold Henisz, the vice dean and faculty director of the ESG Initiative at the University of Pennsylvania’s Wharton School. But that is not necessarily uncommon in the world of equities.

“It’s very hard to ascertain what is an ESG stock in the same way as it is hard to ascertain what is the value stock, what is the growth stock,” Henisz said.

Henisz concluded that definitions and standards will be key to navigating the future ESG landscape: “We need to have more regulation to root out greenwash and really set a standard that if you’re going to say you’re doing ESG integration, you’ve got to meet these criteria.”