A Cubs employee raises the W flag after a Cubs win. The Cubs said the team keeps a large number of W flags on hand, and a new one is used for each victory. A member of the grounds crew is responsible for raising the flag after a Cubs home victory, she said. View Full Caption Flickr Creative Commons

CHICAGO — There's a proper etiquette for flying the "W" flag after a Cubs win.

The flags are flying all over Chicago — and beyond — but perhaps they shouldn't be hanging 24/7.

At Wrigley Field, the white flag with a blue W is raised above the center field scoreboard immediately after a Cubs win at home and typically taken down during the next day's morning commute, according to the Cubs' ballpark operations team. It is not flown from the scoreboard after wins on the road, including Wednesday night's Game 4 victory in the National League Championship Series.

The team keeps a large number of W flags on hand, and a new one is used for each victory. A member of the grounds crew is responsible for raising the flag after a Cubs home victory.

Game-used W flags can be bought on the Cubs Authentics online auction page. The Cubs donate net proceeds from the sale of Cubs Authentics to Cubs Charities, which provides "increased access to sports opportunities and target improvements in health, fitness and education for those at risk," a Cubs spokeswoman said.

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Take your [W] flags down. That's not how this works. Tonight, however, we #FlyTheW — Casey Cora (@bycaseycora) October 19, 2016

The flying the W win flag began at Wrigley Field in 1937. View Full Caption Flickr Creative Commons

The practice of flying the W — or an L for a loss — over the Wrigley Field bleachers scoreboard dates to 1937.

Peter Alter of the Chicago History Museum said the flag was flown to communicate the game's result to fans on the "L" passing by.

“The origins of the W flag, as a way to communicate to fans riding by on the 'L' a Cubs victory, speaks to the neighborhood nature of Wrigley Field and ballparks everywhere for much of the twentieth century," Alter said.

The best-of-seven NLCS is tied at two games apiece with Game 5 on Thursday night in Los Angeles.

The Cubs and Wrigley Field are 95 percent owned by a trust established for the benefit of the family of Joe Ricketts, owner and CEO of DNAinfo.com. Joe Ricketts has no direct involvement in the management of the iconic team.

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