Shares of toy maker Mattel (NASDAQ: MAT) soared on Monday following reports that rival Hasbro (NASDAQ: HAS) had made a recent takeover approach. If an acquisition were to take place, it would create a toy behemoth with more than $10 billion of annual revenue. Shares of Mattel were up about 20% at 11:10 a.m. EST, while shares of Hasbro were up about 6.5%.