Mattel is trading 4.4% higher at $13.88 as of 10:11 a.m. ET on September 28, with no clear company-specific catalyst identified. - Shares rose from the September 25 close of $13.29. - U.S. indices were falling as oil prices and Treasury yields climbed. - The gain most likely reflects company-specific trading rather than the broader market trend, but available evidence does not establish a direct catalyst.