A nasty and personal exchange between Twitter CEO Dick Costolo and an outspoken advocate of women in corporate boardrooms has thrown a spotlight on a serious issue in Silicon Valley: the dearth of women in the upper ranks of America's top technology companies.
The spat began over the weekend when Vivek Wadhwa, a fellow at Stanford's Rock Center for Corporate Governance, wrote on the TechCrunch blog about men dominating Twitter's management ranks. Costolo dismissed the comments — and called Wadhwa "the Carrot Top of academic sources" — but experts said Wadhwa's criticism could go far beyond Twitter.
While there are more high-profile women in prominent positions at top tech companies than even a few years ago, they are still woefully underrepresented.
The leading female executives in Silicon Valley are Yahoo CEO Marissa Mayer, HP's CEO Meg Whitman and Facebook's Sheryl Sandberg. They are all advocates of women having bigger roles in America's top public tech companies.
But when asked why Mayer, Whitman and Sandberg are not more outspoken about the issue of more women on the boards of tech companies, Wadhwa said, "Marissa Mayer is part of the problem. She is part of the old boys network," he added. Yahoo did not respond to requests for comment.
And when you take a closer look at the board of directors of the top 10 tech companies by market cap, not one has more than a few women on their boards.
And while women account for more than 80 percent of Americans' buying decisions and more than 50 percent of the people who use technology, governance pros said there is very little pressure on companies to be more inclusive and diverse in the board room.
Penny Herscher is the CEO of Firstrain, an enterprise software company that provides big data analytics, and she sits on the boards of JDS Uniphase and Rambus. Herscher said it's different in Europe.
(Read more: Here's how much stock Twitter execs own)
In the United Kingdom, there is a goal that 25 percent of the boards of the FTSE 100 companies will be held by women by 2015. Herscher said there is no such effort under way in the United States, and there's little pressure by corporate governance groups to push companies to force the issue of diversity on corporate boards.
"We could create reporting on diversity in management as a means for informing shareholders on the actual diversity in the company," Herscher said, adding that it could be analogous to the way compensation is disclosed in corporate annual reports.
Herscher added that Intel has been a leader in the advancement of women inside its corporation and received the 2013 Anita Borg Top Company for Technical Women Award. Intel also has two women on its board of directors, including former Ambassador Charlene Barshefsky and Susan Decker, formerly of Yahoo.
(Read more: Who'll succeed Microsoft's Steve Ballmer?)
Of the top technology companies in Silicon Valley, Google is the leader of the pack with three women on its board: Diane Greene, who co-founded and is the former CEO of VMWare; Ann Mather, former CFO of Pixar; and Shirley Tilghman, the former president of Princeton University.
Jeffrey Sonnenfeld of the Yale School of Management and a CNBC contributor attributed the lack of women on technology boards to what he calls "a young boys club in the Valley." He added that it's due in part to a group of relatively younger men, who think that Silicon Valley is run as a meritocracy. Sonnenfeld says the young male power players don't think they have to look out for bias issues, but in reality they do.
Sonnenfeld said Twitter would be wise, especially in light of Costolo's less-than-gracious comments, to consider specific candidates for the Twitter board. The women Sonnenfeld mentioned include Sherry Lansing, former CEO of Paramount; Jill Abramson, executive editor of The New York Times; and Anne Moore, the former president of Time Inc.
Twitter did not respond to requests for comment.
In a related matter, AllThingsDigital is reporting that Vivian Schiller, NBC News's chief digital officer, is the lead candidate for Twitter's head of news position.
Wadhwa said he thinks the whole incident and Costolo's comments toward him will be a positive. Wadhwa finished by saying he would be shocked if Twitter didn't add a woman to its board of directors in the very near future.
—By CNBC's Mark Berniker and Josh Lipton. Follow Berniker on Twitter @markberniker and Lipton @CNBCJosh.