A hands-free robotic sex toy won an award for innovation at the Consumer Electronics Show tech show in Las Vegas, but the prize was later revoked.

The Osé personal massager, the startup Lora DiCarlo's first product, originally won the CES Innovation Award in the robotics-and-drones category.

But the Consumer Technology Association, which judges the awards and organizes CES, said the sex toy should never have been considered as it "does not fit into any of our existing product categories."

In an open letter, the CEO of Lora DiCarlo said the association had changed its story.

She said it initially told her it revoked the award on moral grounds, and she accused it of sexism, saying that sex gadgets aimed at men are prominent at CES.

A robotic sex toy had its innovation award revoked at the Consumer Electronics Show in Las Vegas, prompting accusations of sexism.

The Osé hands-free personal massager is the first product made by Lora DiCarlo, a company that describes itself as "a woman-run start-up" that is "determined to change the face of pleasure products."

In an open letter, Lora DiCarlo's CEO, Lora Haddock, said the company submitted the Osé for the CES Innovation Awards — judged by the tech show's organizer, the Consumer Technology Association — and won, but the victory was short-lived.

"My team rejoiced and celebrated," she wrote. "A month later our excitement and preparations were cut short when we were unexpectedly informed that the administrators at CES and CTA were rescinding our award and subsequently that we would not be allowed to showcase Osé, or even exhibit at CES 2019."

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In a statement to Business Insider, the CTA said:

"The product referenced does not fit into any of our existing product categories and should not have been accepted for the Innovation Awards Program. CES does not have a category for sex toys. CTA had communicated this position to Lora DiCarlo nearly two months ago and we have apologized to them for our mistake."

The product originally won in the robotics-and-drones category, and the organization did not explain in its statement why Lora DiCarlo was stopped from exhibiting at CES.

In her open letter, Haddock said that the CTA kept changing its story and that it initially told Lora DiCarlo the Osé had been disqualified on moral grounds, citing this rule:

"Entries deemed by CTA in their sole discretion to be immoral, obscene, indecent, profane or not in keeping with CTA's image will be disqualified. CTA reserves the right in its sole discretion to disqualify any entry at any time which, in CTA's opinion, endangers the safety or well being of any person, or fails to comply with these Official Rules."

Haddock accused CES of sexism, saying gadgets geared toward men's sexuality had become a fixture on the showroom floor.

"A literal sex doll for men launched on the floor at CES in 2018 and a VR porn company exhibits there every year, allowing men to watch pornography in public as consumers walk by," she wrote. CES 2018 also featured robotic strippers with CCTV cameras for heads.

"Clearly CTA has no issue allowing explicit male sexuality and pleasure to be ostentatiously on display," Haddock wrote. "Other sex toys have exhibited at CES and some have even won awards, but apparently there is something different, something threatening about Osé, a product created by women to empower women."

She also said the notion that the sex toy did not fit into the category it was entered in was "even more insulting and frankly ridiculous."

She said the Osé was developed in partnership with Oregon State University's robotics lab, adding that the Osé "is the subject of eight pending patents and counting for robotics, biomimicry, and engineering feats."

"Osé clearly fits the Robotics and Drone category — and CTA's own expert judges agree," she said.

CES and Lora DiCarlo did not immediately respond to Business Insider's request for comment.