Over the last two years, some of the world’s largest institutional shareholders have joined the push for greater gender diversity on corporate boards. From BlackRock to Vanguard, these giant investors say getting more women into board seats just makes good sense, both for society and business.

Now, two other global asset managers have joined this call to action. Earlier this month, the UK-based firms Columbia Threadneedle and RBC Global Asset Management both vowed to vote down board members of businesses that lack women in executive roles. RBC GAM even took it one step further, pledging to vote against committee members of organizations where women didn’t represent at least a quarter of the board (RBC will raise the threshold to 30% in 2022).

To be sure, some firms may find it hard to follow through with diversity and other purpose-led plans right now under the surging business crush of the coronavirus. But experts say that for any time period, the demand for 25% is an important statement—one that puts greater pressure on companies to take gender diversity more seriously. “The quota affects their financials. It affects their core business,” says Alina Polonskaia, global leader of Korn Ferry’s Diversity and Inclusion Solutions practice.

This isn’t the first time a group placed a number on boardroom diversity. In 2010, a consortium of board chairs and CEOs in the UK launched the 30% Club, intending to triple the percentage of women on corporate boards by 2020. They reached their target in 2018, two years ahead of schedule.

The United States, on the other hand, still lags behind. Recent data shows that, as of last year, only 26% of all S&P 500 and Fortune 1000 boards have women directors. And of those firms, only a third have boards where women represent 30% of board seats, according to the Women’s Forum of New York. Less than 3% have reached gender parity. “The change is not going to happen because we expect boards of directors to change the way they think,” Polonskaia says. “The only way we draw change is through structural changes.”

In other words, to move the needle on board diversity, organizations will need to face more actions that have consequences and trade-off decisions for the business, like the 25% quota. But 25% should only be a minimum, experts say; rather, boards see a real boost to their collective intelligence—and thus an organization’s bottom line—when diverse voices make up roughly 30% of directors.

“It’s not about having a token woman on the board,” says Jane Stevenson, global leader for Korn Ferry’s CEO Succession practice and vice chairman of the firm’s Board and CEO Services practice. “It’s about getting great directors on the board with diverse perspectives.”

Indeed, a recent survey from the stock index firm MSCI found that firms with at least three female board members saw consistently higher equity returns than companies with fewer women present in the boardroom.

For her part, Tierney Remick, vice chairman and coleader of Korn Ferry’s Board and CEO Services practice, hopes this move by Columbia and RBC GAM activates a larger conversation about boardroom diversity. The dialogue, she says, should allow boards to think about the skills and experiences they want in the boardroom—and whether those voices represent the voices of all constituencies. “A quarter is a starting point of accountability,” Remick says.

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