What happened

Shares of ThredUp (TDUP -5.11%), the online clothing resale site, were taking off today on news that rival Poshmark (POSH) was getting acquired. Investors took that as a sign that a prospective buyer could appear for ThredUp.

As of 1:42 p.m. ET, ThredUp stock was up 18%, outperforming even Poshmark's 13.3% gain. 

So what

Poshmark, a larger online secondhand clothing site, said last night that it would be acquired by South Korea's Naver, the country's largest internet company and e-commerce platform, for $17.90 in cash, or $1.4 billion.

While the acquisition is just 15% higher than Poshmark's closing price yesterday, it's a 48% premium to the 90-day volume weighted average price.

Naver CEO Choi Soo-Yeon said in a press release: "The combination will create the strongest platform for powering communities and refashioning commerce. Poshmark is the definitive brand for fashion in the United States that provides a social network for buying and selling apparel. Naver's leading technology in search, AI recommendation, and e-commerce tools will help power the next phase of Poshmark's global growth."

Both Poshmark and ThredUp have struggled on the public markets, plunging from their IPO prices, and investors seem to believe that if Poshmark can get acquired, the same thing can happen to ThredUp. 

However, investors may want to be careful with that line of thinking. Poshmark is significantly larger than ThredUp, which has a market cap of just over $200 million, compared to the $1.4 billion Poshmark is getting acquired for. ThredUp also has a somewhat different business model, as it's focused more on the environmental benefit of secondhand clothing, while Poshmark operates more like an online marketplace, where sellers have full control over what they sell. ThredUp, on the other hand, is more like an online consignment shop, where the company chooses what it sells.

Now what

ThredUp's most recent results shows the company continuing to deliver strong top-line growth but is struggling on the bottom line. Revenue grew 27% to $76.4 million, but it still lost $13.4 million in adjusted EBITDA, with its loss margins worse than the year before.

Whether the online resale market can truly disrupt the apparel industry remains to be seen. For ThredUp, it's at least a modestly positive sign for Poshmark to get acquired, but that's not a reason to buy the struggling apparel stock.