Shares of media giant Twenty-First Century Fox Inc (NASDAQ: FOXA) are up 38.7% in 2018, according to data provided by S&P Global Market Intelligence, as the bidding war for the company heats up. Disney (NYSE: DIS) was the company that kicked off the bidding war for Fox, offering in late 2017 to pay $52.4 billion in stock for a treasure trove of assets, including film and TV studios, Fox's Hulu stake, and some cable networks.