The model, who appeared in the controversial music video along with two other models, made the allegations in her forthcoming book My Body, as reported by The Sunday Times.
She writes: “Suddenly, out of nowhere, I felt the coolness and foreignness of a stranger’s hands cupping my bare breasts from behind.
“I instinctively moved away, looking back at Robin Thicke. He smiled a goofy grin and stumbled backward, his eyes concealed behind his sunglasses. My head turned to the darkness beyond the set.”
The 30-year-old model said Thicke’s actions made her feel “naked for the first time that day”, but that she was “desperate to minimise” the incident.
“I didn’t react – not really, not like I should have,” she said.
“I pushed my chin forward and shrugged, avoiding eye contact, feeling the heat of humiliation pump through my body.”
The video’s director, Diane Martel, recalled witnessing the incident and “screamed” at Thicke about his behaviour.
“I remember the moment that he grabbed her breasts,” she said. “He was standing behind her as they were both in profile,” she told The Times.
Martel said that Thicke “sheepishly apologised” for his behaviour. Both women state that Thicke was drunk during filming.
Both the video and lyrics of the song - which include Thicke repeatedly singing, “I know you want it” - were accused of glorifying rape culture, prompting its ban in some university campuses and nightclubs.
The accompanying video shows Robin Thicke, Pharrel Williams and rapper TI fully clothed while Ratajkowski and two other models are half-naked.
Video director Martel said she aimed to subvert power dynamics by having the women ignore and mock the men, but Ratajkowski said Thicke’s actions reminded everyone who really held the power.
“With that one gesture, Robin Thicke had reminded everyone on set that we women weren’t actually in charge,” she said.
“I didn’t have any real power as the naked girl dancing around in his music video. I was nothing more than the hired mannequin.”
In a 2019 interview with GQ, Williams, who co-created and wrote the song with Thicke, admitted he was “embarrassed” about the song, but Thicke defended the song in 2013 saying critics didn’t “get it”.
The Independent has reached out to Thicke’s representatives for comment.
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