A worker unveils a floor mat bearing the logo of Twitter and the symbol on which Twitter's stock will traded (TWTR) on the floor of the New York Stock Exchange (NYSE) on November 7, 2013 in New York City.

Morgan Stanley has a 5.6 percent stake in social media company Twitter, according to a Securities and Exchange Commission filing released Wednesday.

The stake makes the banking giant the second-largest investor in Twitter, behind The Vanguard Group, which had a more than 9 percent stake in the company as of last September, FactSet data show.

According to the filing, Morgan Stanley owned 43.3 million Twitter shares as of Dec. 31. The bank had a stake of 43.72 million shares as of Sept. 30, FactSet data show.

Twitter shares have been on fire this year, surging more than 10 percent in 2019. Last year, the stock rose 19.7 percent to post its third straight year of gains.