What happened

Shares of Guess? Inc. (GES -0.14%) fell 17.8% on Thursday after the clothing retailer's co-founder was accused of sexual misconduct. Late Wednesday, supermodel Kate Upton took to social media to express her disappointment that Guess is "empowering" company co-founder Paul Marciano as its chief creative director.

"He shouldn't be allowed to use his power in the industry to sexually and emotionally harass women," Upton elaborated, using the #MeToo hashtag that has come to signify the recent movement to highlight the prevalence of sexual assault and harassment.

Blue jeans hanging from a store rack

IMAGE SOURCE: GETTY IMAGES.

So what

Marciano, for his part, promptly denied the accusation, telling TMZ that he was "shocked," and claiming "he's never touched Upton, and has never even been alone with her."

"If she has a claim," he added, "there's one place to tell the truth and that's in court or to the police."

Marciano further suggested that Upton -- who was formerly the face of the Guess? brand -- may be motivated by the company's decision to cut ties with her after she began showing up to sets "looking terrible" following late nights.

Now what

Of course, that unflattering bit of speculation hardly does the Guess? brand any favors, and it seems safe to bet that Upton will provide details to back up her assertion in the near future. With that in mind, it's hardly surprising to see investors taking a step back from the company as they wait to see how the situation unfolds.