J.P. Morgan downgraded Alcoa's rating on Thursday and said it was concerned about its valuation after the company's stock price rose sharply. The bank downgraded the aluminum producer's rating from “neutral” to “low grade.” Analyst Bill Peterson did raise his price target from $45 to $50 per share, but that meant there was still room for about 20% decline from Wednesday's closing price. Prior to this downgrade, the company's stock price showed strong performance. Alcoa shares have soared 74% over the past year.

J.P. Morgan downgraded Alcoa's rating on Thursday and said it was concerned about its valuation after the company's stock price rose sharply. The bank downgraded the aluminum producer's rating from “neutral” to “low grade.” Analyst Bill Peterson did raise his price target from $45 to $50 per share, but that meant there was still room for about 20% decline from Wednesday's closing price. Prior to this downgrade, the company's stock price showed strong performance. Alcoa shares have soared 74% over the past year.