Stocks making the biggest moves midday: FirstEnergy, Snap, Kohl's, Best Buy & more

Check out the companies making headlines in midday trading. 

FirstEnergy — The energy stock fell more than 24%, continuing a sharp fall from Tuesday, after the company was embroiled in a corruption investigation in Ohio. The company said that it has received subpoenas as part of the investigation and "we intend to fully cooperate."

Pfizer — The pharmaceutical stock gained 2.3% after the U.S. government announced a deal to pay Pfizer and German partner BioNTech $1.95 billion to produce its vaccine candidate if clinical trials are successful. The agreement would give the U.S. 100 million doses of the potential vaccine.

Snap – Shares slid more than 8% after the social media company said its net loss in the second quarter rose nearly 28% year over year due to long-term investments. The company reported a 9-cent loss for the quarter, which was in line with Street estimates compiled by Refinitiv, while revenue exceeded expectations. 

Kohl's, Macy's — Shares of the retailers both tumbled more than 6% on Wednesday after UBS downgraded both stocks to sell from neutral. The firm said the two companies can no longer rely on third-party partners to help drive growth as the pandemic has permanently changed consumer shopping habits.

Best Buy — Shares of the electronics retailer surged nearly 8% after the company announced online sales were up 255% for fiscal second quarter 2021 on a year-over-year basis. Overall sales through July 18 were also up about 2.5%.

iRobot – Shares of iRobot dropped more than 6% after the automatic vacuum maker posted big earnings beat. iRobot said it earned $1.06 per share in the previous quarter, significantly higher than the 29 cent consensus estimate per Refinitiv. The company also raised its revenue forecast due to a surge in demand amid the pandemic.

Biogen – Shares of Biogen rose more than 1% after the drug maker reported better-than-expected quarterly result. It posted an EPS of $10.26, compared to a consensus estimate of $8.03. Biogen said it benefited from about $100 million in accelerated sales due to the pandemic.

NVR, Toll Brothers – Shares of homebuilders surged after data showed existing home sales jumped the most in history in June. Sales of existing homes jumped nearly 21% in June, marking the largest monthly gain on record, according to the National Association of Realtors. NVR soared nearly 10%, while KB Home and Toll Brothers also jump 7% each.

Spotify – Shares of the music streaming company advanced more than 4% after striking a long-term licensing deal with Vivendi's Universal Music Group, according to a report from The Wall Street Journal. The deal would reportedly result in Spotify collecting revenue for its analytics information, among other things.

— CNBC's Maggie Fitzgerald, Pippa Stevens, Jesse Pound and Fred Imbert contributed reporting.

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