Can you copyright an atmosphere?

NEW YORK – Oversized beige cable knit sweater. Hair parted in the center. The right knee pointed, creating a curve at the left hip.

Virtually every detail in the photo—right down to the matching short set—looked familiar to Ms. Sydney Gifford. So did the woman posing in front of the nondescript white wall.

A few days ago, Ms. Gifford, a 24-year-old lifestyle influencer, shared a photo with her thousands of followers that was virtually identical. The woman in this new photo was a fellow influencer, Ms. Alyssa Sheil, who she went shopping with and did a photo shoot with months ago.

At the time, she believed their interactions had simply been awkward. But as she scrolled through Ms. Sheil’s Instagram photos for the first time in nearly a year, she said, Ms. Gifford suspected those encounters were a kind of aesthetic espionage.

Ms Gifford claims Ms Sheil, 21, not only started impersonating her persona online, but also appropriated the entire look. And now he’s suing.

Ms. Gifford copyrighted several of her social media posts in January after noticing similarities between Ms. Sheil’s posts and her own. Several photos were introduced as evidence in Ms. Gifford’s 2024 lawsuit in a Texas federal court accusing Ms. Sheil of copyright infringement. But in the watchful world of social media, Ms. Gifford launched a perhaps more severe charge against her: her theft.

“It’s no coincidence,” Ms. Gifford, who has about 300,000 followers on Instagram and more than 500,000 on TikTok, recalled thinking. “There’s definitely something going on here.”

What might appear to be a superficial fight over sweaters and hairstyles could actually be a legal battle that gets to the heart of social media influence. The very nature of successful trendsetting requires some degree of replication. As much as platforms like TikTok and Instagram may seem like a free-for-all, lifestyle influencers exist in an ecosystem that prizes homogeneity—one of the surest ways to appease the algorithms that are the ultimate arbiters of their online success.

As the creator economy grows, teasing the possibility of a profitable livelihood, Ms. Gifford’s case seeks to clarify the line where imitation can turn from flattery to fake.

In several interviews beginning in August, experts said influencers must navigate a murky landscape where assigning credit to who created what can be daunting or sometimes impossible.

“There’s really a sense that you’re both a creator and a borrower,” said intellectual property law professor Jeanne Fromer of New York University. “Fashion is based on that. All creative industries – painting, music, movies – are all built on borrowing in some way from the past and also ideally trying to put your own spin on something. I don’t know that anyone wants to go too far as a result.”

Ms. Sheil said Ms. Gifford’s claims about her posts were unfounded and that she found them deeply upsetting as an influencer in her own right.

“This is how I make a living and not only that, this is my personal brand,” Ms. Sheil said in an interview. “I feel like I have to defend myself.”