Pinterest reportedly files confidentially for an IPO

Put this on your pinboard: Pinterest, the social bookmarking site, is reportedly planning to go public this year.

On Thursday, Pinterest confidentially filed paperwork with the US Securities and Exchange Commission for an initial public offering, according to The Wall Street Journal, citing people familiar with the matter. The company expects to seek a valuation of at least $12 billion, the Journal reported. 

"We don't comment on rumor or speculation," a Pinterest spokeswoman said in a statement. 

Pinterest is among other highly valued startups in the Bay Area planning to list their shares on the stock market in 2019. Ride-hailing services Lyft and Uber along with Airbnb and Slack are expected to go public this year.

Founded in 2010, Pinterest has more than 250 million monthly active users as of September. People use the site to search and save images, helping them to plan their dream wedding and vacation or find clothing or furniture they want to buy. 

Andrew Lipsman, an analyst for eMarketer, said in a statement that the industry "will be watching closely to see if it can withstand scrutiny as a public company."

Nearly 40 percent of US social network users are on Pinterest, according to eMarketer.

"Pinterest has a strong argument to make as an advertising platform because of its visual nature and the aspirational way in which users engage," Lipsman said. "Ultimately, it will have to prove that its ads are effective in building brands and driving commerce."