Goldman Sachs analyst Matthew Korn upgraded Allegheny Technologies to Buy from Neutral with an unchanged price target of $25. Allegheny is one of few stocks in the sector with sales growth that does not depend on a commodity price recovery, Korn tells investors in a research note. The stock's valuation discount created by softness in certain secondary end-markets and uncertainty created by the 737 MAX grounding has created a buying opportunity, adds the analyst. He believes the fundamental driver of Allegheny's "attractive growth "profile remains intact, namely growing global demand for modern jet engines that require highly-technical specialty metal components.