Mr Dorsey posted the news of the purchase on Twitter on Friday, sparking a one per cent gain in the company's share price in after-hours trading, TechCrunch reported.
The documents filed with Securities and Exchange Commission (SEC) showed Twitter CEO purchased 574,002 shares of Twitter stock at roughly $16.62 each.
"That price is either a steal, if you compare it to Twitter's peak share price of almost $70 or a pretty bad deal if you're looking at last week's share price that was $2 lower," the report noted.
Earlier this week, Twitter claimed that it has brought in $548 million in revenue in first quarter of current year, beating investor expectations of $511.9 million.
But according to media reports, Twitter has not been able to make much from his purchase of over 400,000 shares back in February.
Twitter has so far purchased over one million additional shares in 2017 alone.
Mr Dorsey had also bought a small share in August 2015 -- shortly after he became Twitter's interim CEO.