Ratings agency Moody's has agreed to pay more than $16 million to resolve charges tied to its assessment of residential mortgage-backed securities worth tens of billions of dollars, market regulators announced Tuesday.
The case also involved the first charges brought by the Securities and Exchange Commission involving deficient ratings symbols.
It comes nearly 10 years after the global financial crisis, in which the improper rating of such securities played a starring role.
According to the SEC, Moody's failed to establish and enforce proper internal controls for models used to rate mortgage backed securities between 2010 and 2013.
As a result, the agency, one of the largest in the United States, corrected more than 650 ratings of mortgage-backed securities valued at more than $49 billion, according to the SEC.
In 54 cases, Moody's rated securities differently than its own models suggested it should but kept no record of its reasons for doing so, the commission said.
The agency also issued 26 ratings of securities called "combo notes" valued at about $2 billion in a manner the SEC said was inconsistent with ratings of other securities using the same ratings symbols.
"As our order notes, the SEC put Moody's on notice about its internal controls obligations yet it did not develop an effective process to ensure the accuracy of the models it relied upon when rating residential mortgage-backed securities," Antonia Chion, the SEC's associate director of enforcement, said in a statement.
Moody's neither admitted nor denied wrongdoing.
Investors rely on such ratings to assess the creditworthiness of loans backing some derivative securities.
A congressionally mandated inquiry in 2011 said that ratings agencies had played an "essential" role in fomenting the 2008 financial meltdown on Wall Street -- and accused Moody's in particular of internal "breakdowns" in which the company systematically gave its highest rating to toxic assets that later crashed.