NEW YORK (TheStreet) -- RATINGS CHANGES

American International Group (AIG) - Get Report was downgraded to hold at TheStreet Ratings. You can view the full analysis from the report here: AIG Ratings Report.

Knowles (KN) - Get Report was initiated with a sell rating at TheStreet Ratings. You can view the full analysis from the report here: KN Ratings Report.

Navistar (NAV) - Get Report was downgraded at Morgan Stanley to underweight. Twelve-month price target is $20. Company has had execution issues and could fail to meet forward expectations, Morgan Stanley said.

St. Jude (STJ) was downgraded at Wells Fargo to market perform from outperform. Company is facing increased competition in its core business, Wells Fargo said.

Virgin America (VA) was initiated with an underweight rating at Credit Suisse. Twelve-month price target is $31. Company has a less attractive growth profile and is vulnerable to competition, Credit Suisse said.

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This article was written by a staff member of TheStreet.