Before Wednesday's open, Goldman dropped the health website operator's rating to "sell" from "neutral." In an updated note, the firm said it was reverting WebMD to a "neutral" rating, noting that it erroneously included convertible notes when calculating diluted share count and net debt.
WebMD slipped in early trading but later climbed higher following the amendment. The stock last traded 2 percent higher around $48 per share.
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Goldman's current price target is $57 per share.
— CNBC's Peter Schacknow contributed to this report