Bed Bath & Beyond Inc.'s 349% three-week increase defies warnings from Wall Street banks about the firm's high valuations and has rekindled a wave of meme stock buying.

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The stock continued to rise on Tuesday, reaching a high of 79%, before cutting gains to 29% and closing at $20.65 following two trading halts.

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According to Bloomberg data, the stock was the most actively traded one, with 385 million shares changing hands—more than 20 times the three-month average.

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In spite of at least three Wall Street banks downgrading the home goods company and advising investors to sell the shares due to the "meme stock frenzy," the stock has risen.

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Earlier on Tuesday, Susan Anderson of B Riley Securities downgraded the retailer's $1.65 billion value to "unrealistic," and changed her recommendation to "sell."

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Before the stock's most recent spike, Baird's Justin Kleber downgraded shares, saying that the "fundamental risk/reward looks unappealing" due to the company's increasing market share losses and capital burn.

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Despite this, retail traders continued to buy heavily, pushing $99 million into the stock since July 26. This is according to statistics provided by Vanda

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The stock rose 24% on Monday to close at its highest level since late April, contributing a record $46 million to the net inflow, according to the statistics.

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Some investors are banking on the shares to rise further. Call options betting on the stock to trade above $45 by the end of the week, alongside other contracts betting on a rise to $80 by mid-January,

IMG source  Google