The stock jumped as high as 30 percent in opening-day trade, at one point giving it a market value of about $13 billion.
The milk-alternative company already has some street cred thanks to backing from entertainment A-listers such as Oprah Winfrey and Jay Z. It also has a supplier contract locked down with Starbucks.
Oatly is credited for jump-starting demand for oat-milk and is widely credited for popularizing it in several countries. It now sells in more than 20 markets across Europe, the United States and China and is so popular in some places that it has faced supply shortages.
The $1.4 billion raised from the IPO will be used to help address those bottlenecks and fuel further expansion.
Plant-based foods have quickly grown in popularity, especially among millennials and generation Z consumers, who are not shy in backing healthy and environmentally-friendly brands.
Oatly is not the first animal-alternative company to go public. Beyond Meat, with its faux burgers, made its stock market debut two years ago and has since seen its stock price quadruple... And sources tell Reuters, Impossible Foods is prepping a public listing, which could value the fake-meat company at around $10 billion.
Shares of Oatly closed the day with a near 19 percent gain.
