CHICAGO --The city of Chicago is suing eBay and StubHub over ticket sales to some events in the city. The lawsuit claims the two firms are reseller agents and required to pay an amusement tax. Both companies dispute that claim. eBay bought StubHub last year. Chicago officials are asking the companies to hand over records of sales in Illinois to determine how many tickets the companies sold. If the city wins the lawsuit, people who buy tickets on eBay and StubHub could pay an extra eight percent tax.