A San Francisco clothing company is suing Ivanka Trump’s fashion brand, claiming in a class-action lawsuit filed last week that the brand gained an unfair advantage with the election of Trump’s father as president of the United States.

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In the lawsuit, filed Thursday in San Francisco Superior Court, attorneys for Modern Appeal Clothing claimed that Ivanka Trump Marks LLC got an unfair boost by “Donald J. Trump being president of the United States and from Ivanka Trump and her husband, Jared, working for the president of the United States.”

The brand is “exploiting the power and prestige of the White House for personal gain,” the lawsuit claims.

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Attorneys for Modern Appeal Clothing pointed specifically to statements made by White House adviser Kellyanne Conway, President Donald Trump and White House press secretary Sean Spicer.

Donald Trump slammed Nordstrom on Twitter in February after the luxury department store dropped Ivanka Trump’s brand. The tweet was also shared to the president’s official @POTUS account.

Spicer defended the tweet later that day, telling news media that Donald Trump “has every right to stand up for his family and applaud their business activities, their success.”

In an appearance the next day on Fox News, Conway encouraged people to buy Ivanka Trump’s clothing brand, sparking calls for an investigation into whether the comment constituted an ethics violation.

"Go buy Ivanka's stuff," Conway said. "I'm going to give a free commercial here. Go buy it today, everybody. You can find it online."

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The class-action lawsuit, filed on behalf of women’s clothing retailers across California, seeks unspecified damages and court costs along with a restraining order that would bar the sale of Ivanka Trump’s products in California.

Modern Appeal Clothing was founded in 1980, according to the San Francisco Chronicle. The brand operates a pair of shops in San Francisco.