Mortgage lenders reported solid increases in loan originations during the third quarter of 2012, leading to a surge in securitization activity at Fannie Mae and Freddie Mac. Single-family mortgage originations totaled $475.0 billion during the third quarter, according to a new Inside Mortgage Finance analysis. That was up 9.2 percent from the second quarter of the year and marked the highest quarterly origination volume since the end of 2010, when an earlier refi surge pushed production to $520.0 billion. The strong third quarter suggests...[Includes two data charts]