The moment Nike unveiled Caitlin Clark’s official logo, the sports world—and retail world—was thrown into a frenzy. What might have been just another athlete branding initiative became an unprecedented phenomenon almost overnight. Stores across the country began selling out, online platforms reported record-breaking numbers, and fans flooded social media with excitement, memes, and reactions to the merchandise. Industry insiders quickly labeled the surge the “Clark Effect,” a phenomenon rarely seen even among the most iconic athletes in sports marketing history.