Twitter announced Thursday that it has filed paperwork to begin the process of become a publicly traded company.

The firm made its announcement in a Twitter message at 5 p.m., Eastern. “We’ve confidentially submitted an S-1 to the SEC for a planned IPO. This Tweet does not constitute an offer of any securities for sale,” the company said in message on its social network feed.

The JOBS Act, passed last year, allows for “emerging companies” to file for an IPO in a confidential process with the Securities and Exchange Commission. Emerging companies, according to the law, are defined as those that make less than $1 billion in revenue.

Twitter’s documents can remain confidential for up to 21 days, under the law, before the company goes on its IPO “road show.”

The company declined to comment, apart from its tweet. Analysts have previously estimated that the company’s IPO could be valued at around $10 billion. But the stock was trading closer to $15 billion on private markets following the announcement, said Wedbush Securities analyst Michael Pachter.

Twitter, which was founded in 2006, celebrated its seventh birthday in March and has quickly emerged as a central forum for public discussion.

Earlier this year, the company reported that its 200 million active users now send around 400 million tweets per day. The company has been focused on getting high-impact users to join its network, such as the former Pope Benedict, who passed on his “@Pontifex” Twitter handle on to his successor, Pope Francis.

The company also won plaudits from free-speech advocates and others when articles in The Washington Post and The Guardian indicated that while its tech peers, including Facebook, Google and Apple, were involved in a National Security Agency surveillance programs, Twitter was not.

The firm has, however, has wrestled with issues of protecting free speech and expression while also complying with local speech laws, and does prevent some content from being seen in certain countries.

The network has also emerged as a critical advertising and marketing platform in recent years. Commentary on Twitter during the Super Bowl has become nearly as important as the game and its commercials — Oreo, for example, earned praise from marketers for using the platform to quickly respond to a blackout at the 2012 Super Bowl.

Politicians and lobbyists have also used the service as a sort of megaphone. As The Washington Post reported, groups such as the National Rifle Association, the AARP, Chevron and Microsoft all bid to have ads for their organizations show up alongside the hashtag “#SOTU” during the last State of the Union address.

The company’s ability to generate advertising revenue will be a key concern for those that may consider investing in IPO. The firm has been experimenting with different ways to engage with its millions of users in recent months by launching new types of ads, as well as more focused services such as Twitter Music. The company has also been changing how it identifies conversations on the site — a tweak many saw as an effort to make the site more accessible to new users.

Ahead of its Thursday announcement, the firm said that it will make it easier for some of its users to filter messages they receive, in order to improve the quality of conversations.

More tech news:

The Switch: The Twitter IPO is finally here!

Apple’s new iPhones: Where the rumor mill got ahead

Photos: Apple unveils new iPhones

Follow The Post’s new tech blog, The Switch, where technology and policy connect.