Bloom Energy Corp. stock /zigman2/quotes/209802424/composite BE -4.64% was downgraded to sector weight from overweight on Thursday, with analysts wary of the volatility expected to follow news of a major restatement of financials late Wednesday. The fuel-cell company said it expects to restate results dating back to 2016 because of an accounting error relating to revenue recognition. The news sent the stock down more than 20% in after-hours trading, and down about 10% Thursday. the stock has gained about 230% since KeyBanc started covering it in October. " As shares edge toward our near-term bull case ($14), we expect more NT volatility, driven by restatements," analysts led by Sophie Karp wrote in a note to clients. "Our discussions with BE indicate the issue is limited in scope and related solely to recognition of MSA revenue. That said, the market will nonetheless react negatively in the NT due to this overhang." The stock has been volatile in the past, plummeting from a $15 IPO issue price to less than $3 a share last fall amid a short-seller’s report that called the company's accounting into doubt and new clean-energy standards that shut the company out. Shares are down 14% in the last 12 months, while the S&P 500 /zigman2/quotes/210599714/realtime SPX -0.50% has gained 23%.