The British Airways i360 attraction must no longer claim it is the world's tallest moving observation tower after the advertising watchdog ruled it was "misleading".
The Brighton structure, which was designed by the same team behind the London Eye, holds the Guinness World Record for the most slender tower with a diameter of 13ft (3.9m) at its widest point.
But it can no longer claim it is the world's tallest moving observation tower after the Advertising Standards Authority (ASA) upheld a complaint that there were a number of other observational towers with moving platforms that were taller.
Brighton i360 said they did not claim to have the highest moving observation tower but the tallest, defined as "measuring a specified distance from top to bottom".
They said the "tallest moving observation tower" referred to the distance from which the pod travelled - from ground level to 138 metres - a greater vertical distance than any other moving observation tower.
They added there was no evidence any consumer had been misled by their claim.
The ASA said consumers would understand "the world's tallest moving observation tower" to mean the observation desk rose to a height higher than any other moving observation tower in the world.
It said: "We noted the British Airways i360 moved a greater distance from the ground up than other towers.
"However, while the evidence provided by British Airways i360 showed that other moving observation areas rose from halfway up a tower structure and not from the ground, we noted that those towers rose higher into the air than the British Airways i360.
"Because we did not consider the British Airways i360 was taller than other observation towers in the way that consumers would understand it, we therefore concluded the ad was misleading."
Steve Bax, executive director of British Airways i360, said: "British Airways i360 has received multiple prestigious awards for innovation, design and the quality of our visitor experience, and while the ASA ruling was disappointing it does not change our position as a world-class attraction which is giving inspiration and delight to hundreds of thousands of people every year."