Spreads on mortgage-backed securities with non-qualified mortgages have tightened in recent years, according to S&P Global Ratings. “Since non-QM deals first appeared in 2014, their AAA spreads have tightened, suggesting that the market may be growing more comfortable with this asset class,” the rating service said. The spread measures the price of MBS tranches compared with a benchmark international swap rate. Tighter spreads indicate greater demand from investors ...