Nearly 36,000 Robinhood users added Pfizer shares Wednesday after the US government ordered 100 million doses of its coronavirus vaccine

• In the last 24 hours, nearly 36,000 Robinhood traders have added shares of Pfizer, according to data from Robintrack.net.
• Pfizer and BioNTech announced Wednesday that the US government had placed an order for 100 million doses of its coronavirus vaccine.
• Shares of Pfizer surged 5% on Wednesday.
• Watch Pfizer trade live on Markets Insider.
• Read more on Business Insider.

Robinhood traders piled into Pfizer stock Wednesday following positive news about its coronavirus vaccine.

In the last 24 hours, nearly 36,000 Robinhood day traders added shares of Pfizer, according to data from Robintrack.net. It's the most-added stock on Robinhood in the last day, with more accounts adding the pharmaceutical company than Tesla or Snap.

Shares of Pfizer surged 5% Wednesday after the company announced that the US government had placed an initial order for 100 million doses of the coronavirus vaccine it's developing with BioNTech, a German biotech firm.

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BioNTech surged 14% on Wednesday, and more than 7,000 Robinhood traders picked up shares of the company in the last 24 hours, according to Robintrack data. It's the third most-added stock on the platform on Wednesday, according to the site's popularity ranking.

Following Wednesday's added shares, Pfizer is the 48th most popular stock on the trading platform and is held by more than 163,000 accounts.

Retail trading has seen an influx in recent months as markets recovered from the coronavirus pandemic meltdown in March. Traders have been piling into bankruptcy stocks, tech companies, and more via zero-fee brokers such as Robinhood, Charles Schwab, and TD Ameritrade.