JeQuan Lewis #1 of the Virginia Commonwealth Rams shoots as he defended by Jae'Sean Tate #1 of the Ohio State Buckeyes in the second half during the second round of the 2015 NCAA Men's Basketball Tournament at Moda Center on March 19, 2015 in Portland, Oregon. 
JeQuan Lewis #1 of the Virginia Commonwealth Rams shoots as he defended by Jae'Sean Tate #1 of the Ohio State Buckeyes in the second half during the second round of the 2015 NCAA Men's Basketball Tournament at Moda Center on March 19, 2015 in Portland, Oregon.  - 
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About 60 million Americans filled out brackets to predict the outcome of the NCAA Men’s Basketball Tournament. It's also estimated by Challenger, Gray & Christmas that the productivity drop during the three-week tournament is $1.9 billion.

That isn't all that's on employers’ minds, though. Workplace pools can also lead to trouble with organized labor.

“I sort of do it on my own time and I suggest that employers do not allow it to run rampant," says Gary Lieber, an attorney at FordHarrison who represents management in labor cases and warns that allowing bracket bets in the workplace could violate what's known as the "no-solicitation rule."

"Work is work,” he says. “An employer can demand that employees spend all of his work time dedicated to the employers' operations."

That means no work-time solicitation in companies that bar it, and that's where unions get a little defensive. Matt Ginsburg, associate general counsel for the AFL-CIO, says employers often have a double standard when it comes to enforcement. He says in one case, a judge found against an Indiana hospital for interfering with nurses organizing a union, while ignoring other violations.

"He found examples that included solicitations for Girl Scout cookies, March of Dimes, United Way, Secretaries' Day, Boss Day, and going-away parties," Ginsburg says.

So could March Madness pools be included on that list?

"If an employer is promoting a March Madness pool,” he says, “I think that can be a form of solicitation, yes."

He says the AFL-CIO has yet to file any complaints regarding a March Madness pool, but like in the tourney, there is no such thing as a sure thing. I'm looking at you, Kentucky fans.