In the TV ads, which carried the "it's life proof" tagline, the Defy handset was dropped in a nightclub and splashed at a pool party.
The Advertising Standards Authority (ASA) banned the ad after ruling Motorola misleadingly exaggerated the durability of its products, following three complaints from viewers who cracked their phones after dropping them accidentally from the height shown in the ad.
Motorola defended the claims that its phone was life proof after saying the complainants' experiences were not indicative of a wider problem.
The phone manufacturer backed up its arguments with its own testing results, which subjected the handset to around 300 drops.
It claimed the Defy was more durable than its other ranges and competitor products because there was only a 1.5% probability of the product failing due to material damage, functional failures and cracks in a drop from the height shown in the ad.
However, the ASA banned the ad because it believed the creative falsely implied the Defy would generally withstand damage in the scenarios depicted.
The advertising watchdog came to its conclusions after dismissing the protestations of Motorola because it had not seen evidence that dropping the phone from the height depicted in the ads would not cause damage.
In August, Motorola again came under scrutiny, when the regulator told the phone company to stop describing its Atrix model as the "world's most powerful smartphone".
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