The Confederate League of the South said Lamar Advertising Co. took down the billboard along Interstate 85 in Montgomery following complaints. The billboard had the word "secede" in capital letters, along with the group's name and website.
The sign went up Friday and was removed over the weekend, league president Michael Hill said.
"I checked my email Saturday and I had an email from Lamar Advertising saying they had gotten complaints and had other customers who were threatening to quit doing business with them if they didn't take it down," Hill said. "It was gone by mid-Sunday morning."
A Lamar Advertising executive did not return a message seeking comment. The league started an online petition asking the company to reinstall the billboard.
Hill said the company offered a refund, but that wasn't necessary since he had yet to pay.
The league advocates conservative positions and supports Southern states leaving the United States.
The Alabama-based group erected the same billboard in Tallahassee, Florida, and the Florida Chamber of Commerce and Independent Colleges and Universities of Florida responded last month by putting up a billboard nearby with the words, "Succeed Florida!"
Hill said the "secede" billboard cost about $2,000 in Florida, and he didn't have a problem with the Florida business group and the college organization putting up a response.
"We welcome the argument," Hill said. In Alabama, "it's a squelching of dissent issue."
Hill said the league next hopes to place the billboard northeast of Atlanta.
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