Dorsey bought 574,002 Twitter shares in multiple transactions at prices ranging between $16.47 and $16.74 per share, according to the filing. http://bit.ly/2oUhQFO

That adds to the roughly $7 million worth of Twitter stock Dorsey bought earlier this year, bringing the total number of shares he has purchased this year to 1 million, the CEO said in a tweet.

According to the filing, Dorsey now owns about 16 million Twitter shares, which equates to a stake of about 2.2 percent in the company he co-founded.

Dorsey's disclosure comes a day after Twitter reported better-than-expected user growth for its first quarter, following several quarters of stalled growth.

Twitter's shares rose 1 percent to $16.65 after the bell on Friday.

The stock closed up nearly 5 percent in regular trading on Friday, adding to a gain of roughly 8 percent on Thursday when the company reported its results.

(Reporting by Narottam Medhora in Bengaluru; Editing by Savio D'Souza)