Twitter and Square CEO Jack Dorsey speaks during a press event at CES 2019 on January 9, 2019 in Las Vegas, Nevada.

Twitter says it paid co-founder Jack Dorsey a salary last year for the first time since he returned to his post as CEO in 2015.

The billionaire was paid a symbolic sum of $1.40 in 2018, the firm said in a regulatory filing Monday, a nod to Twitter's old 140-character tweet limit.

Twitter's reasoning? It's "a testament to his commitment to and belief in Twitter's long-term value creation potential."