Wall Street wasn't able to extend Monday's celebratory mood into Tuesday, as a slump in tech stocks weighed on the market as a whole. Losses for the broad-based S&P 500 weren't too severe, but the Nasdaq Composite saw a much bigger pullback. Even with some of the immediate macroeconomic and geopolitical concerns about a possible trade war having moved to the back burner, issues like rising tensions between Russia and the rest of the world have created an overhang of anxiety among investors. Adding to the negativity was bad news affecting several companies. Twitter (NYSE:TWTR), Overstock.com (NASDAQ:OSTK), and Geron (NASDAQ:GERN) were among the worst performers on the day. Below, we'll look more closely at these stocks to tell you why they did so poorly.

Twitter takes its turn

Shares of Twitter plunged 12% as the microblogging social media company joined its peers in responding negatively to recent controversy over the use of data collected through the budding technology. Piling on was short-selling specialist Andrew Left at Citron Research, who said that Twitter could be a bigger loser than its industry peers if Congress or state lawmakers try to impose new privacy regulations on the social media business. The move is more notable because Citron had issued what for it was a relatively rare bullish call on the stock fairly recently. Until the dust settles on what the regulatory environment for Twitter will look like, share prices will likely remain volatile.

Twitter logo of blue bird flying and singing.

Image source: Twitter.

Overstock.com sells low

Overstock.com stock dropped 15% after the e-commerce specialist and newly transformed cryptocurrency play announced a secondary stock offering. The company said late Monday that it would sell 4 million shares, which represents roughly 13% of the company's outstanding shares and about 20% of its current float in the public markets. The sad thing for Overstock is that its stock has plunged by more than half since early January, and it therefore missed the best time it could have raised cash through an offering. With bitcoin and other cryptocurrencies going through a slump, now didn't seem to be the best time for Overstock to do an offering unless it had no other choice strategically.

Geron draws skepticism

Finally, shares of Geron fell 14%. The stock has seen incredibly strong upward movements so far in 2018, with many investors excited about Geron's prospects for its imetelstat treatment for cancer. Yet one analyst today expressed a negative counterpoint in an evaluation of Geron's potential, suggesting that imetelstat's performance doesn't entirely warrant the optimism that investors have shown in driving the shares higher. Still, those who are bullish on the stock believe that a quick application for approval for the drug could come in short order, justifying the big move higher. Even with today's drop, Geron stock has still doubled in March alone.

Dan Caplinger has no position in any of the stocks mentioned. The Motley Fool owns shares of and recommends Twitter. The Motley Fool has a disclosure policy.