Charlie Company Is Headquartered in Wisconsin

Charlie Company is headquartered in Wisconsin.Charlie Company's auditors are headquartered in Minnesota.Bob lives in Bloomington,Indiana but works in Chicago,Illinois.Based on a tip from his boss,Bob calls his stockbroker (Jim,who offices in Chicago)and instructs him to purchase 1,000 shares of Charlie Company despite never having requested or reviewed Charlie Company's financial statements.Charlie Company is traded on the New York Stock Exchange and the transaction takes place 15 minutes later on the floor of the exchange.
Charlie Company declared bankruptcy three months later and Bob lost his entire investment.Bob sued Charlie Company's auditors for ordinary negligence.
The trial is scheduled for hearing in Madison,Wisconsin.Before the opening of the trial,the attorney for the auditors objects to the trial being held in Wisconsin,since the transaction between Bob and Jim took place in Illinois.The attorney asks that the trial be moved to Illinois.
Required A.Why would the attorney ask for the trial to be moved?
B.What defense would you raise if you were the auditors' attorney?