Qualcomm announced a mixed set of first quarter results, hit by “legal and regulatory challenges” which drove net profits down 36% year-on-year to $700m. Most of the decline was down to one-off items such as the recent ruling on historical royalty payments to BlackBerry, and the $868m file imposed by South Korea’s antitrust authorities. An arbitration ruling has ordered a payment of $815m in repayments to Blackberry and Qualcomm also cited another ongoing royalty payments dispute with an unnamed customer. And more such financial blows may follow, depending on the outcome of Qualcomm’s current legal battle with Apple, and probes of its business practices in the US, European Union and Taiwan. Qualcomm CEO Steve Mollenkopf said on the analyst call…