Elon Musk's Twitter moves drove the biggest 2-day push by retail traders into the social media platform on record, research firm says

• The revelation of Elon Musk's big stake in Twitter sparked the biggest two days of buying of the stock by retail investors.
• Individuals bought a combined total of $348 million of Twitter shares on Monday and Tuesday.

This week's revelation that billionaire investor Elon Musk has become the largest shareholder in Twitter kicked off the largest buying spree of the company's stock by retail investors, according to tracking firm Vanda Research.

The social media platform's stock drew in the largest inflow of purchases ever from the retail crowd on Monday and Tuesday with a combined tally of $348 million, said the firm whose VandaTrack tool monitors retail flows in US stocks and exchange-traded funds.

"Elon's at it again, this time taking on Twitter from within – and retail is liking it," Vanda researchers Marco Iachini and Giacomo Pierantoni wrote in a note Wednesday.

Twitter's stock soared 27% on Monday after Musk reported to the Securities and Exchange Commission his 9.2% stake in the company. His take of 73,486,938 shares made him Twitter's largest shareholder and his holding was worth $2.89 billion based on Friday's closing price of $39.31 a share. Musk, who is the boss at Tesla, is joining Twitter's board until 2024.

"Twitter - hated or loved by its users - has severely lagged other tech peers in the past year even despite Monday's rebound … making it a great candidate for contrarian retail buying," said Vanda. The researchers noted Twitter's stock at one point this year had lost 24% compared with the FANG+ index's year-to-date loss of 1%. Twitter's year-to-date decline has since narrowed to roughly 17%.

Musk on Monday evening posted a poll on Twitter asking his nearly 81 million followers if they wanted an edit button. Twitter said Tuesday it's been working on an edit feature since last year and that it plans to begin testing it in the coming months. "No, we didn't get the idea from a poll," wrote Jay Sullivan, head of consumer product at Twitter.

An updated SEC filing Tuesday showed Musk has been purchasing Twitter stock since January and that's he reached an agreement to limit his stake in Twitter to 14.9% for as long as he serves as a board member and for 90 days after that.

"Elon Musk has been heavily critical of the company in the past despite being a heavy user. As he's quite the personality, particularly among retail (and crypto) investors, we can easily imagine that TWTR will be heavily susceptible to buying/selling in the future based on Elon's communications (just as with Tesla shares)," said Vanda.

Musk on Tuesday tweeted he's looking forward to working with Twitter CEO Parag Agrawal and the board "to make significant improvements to Twitter in coming months!"