• Activist investor Barington Capital is pushing Mattel to consider selling off its American Girl and Fisher-Price brands, citing underperformance within the divisions.
• Mattel shares trade at the same levels they did more than 20 years ago, but jumped on the news.
• Barington has pursued campaigns at Bath & Body Works, Darden Restaurants and Chico's.

Activist investor Barington Capital is pushing Mattel to consider selling off its American Girl and Fisher-Price brands, citing underperformance within the divisions.

Mattel shares gained 4% in Friday trading following a letter sent to Mattel on Thursday, which was first reported by The Wall Street Journal. The toymaker's shares trade at roughly the same level as they did 20 years ago. Barington has an undisclosed stake in the company.

American Girl and Fisher-Price, two iconic brands, are among the most popular in their respective markets.

While the broader market has grown for the kind of toys that Fisher-Price makes, Barington's James Mitarotonda said in the letter to CEO Ynon Kreiz that Fisher-Price's revenue has fallen from $1.9 billion in 2015 to less than $1 billion by 2023.

Mitarotonda said that if Mattel cannot stymie continued erosion in both Fisher-Price and American Girl, which has suffered similar declines, the company "may not be the right owner of these brands."

Barington suggested the company should "immediately" explore strategic alternatives for those two segments.

"We believe that these brands are now detracting from the success at Mattel's other segments and hurting shareholder value," Mitarotonda said in a release.

A Mattel spokesperson said in a statement to CNBC, "We look forward to engaging with Barington as we do with all our shareholders. We welcome this initial outreach and we are reviewing their letter." 

The letter also highlighted "excessive" stock-based compensation that was higher than a group of peer companies, and claims Mattel continues to add back share-based compensation to the company's adjusted EBITDA, a practice Barington called "shocking."

Barington also told Kreiz that the company should pause continued merger and acquisition efforts in favor of a $2 billion share repurchase operation, which would be an expansion of the company's existing share buyback program, and elevate lead director Michael Dolan to chair, a position Kreiz currently holds.

Dolan is the former CEO of Bacardi, IMG and Young & Rubicam, an advertising firm.

Barington has pursued campaigns at Bath & Body Works, Darden Restaurants and Chico's. It was founded in 2000.

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