Block.com, founded by Twitter co-founder Jack Dorsey, reported $2 billion in Bitcoin revenue in the third quarter, accounting for nearly a third of its total revenue. According to Block.com's Q3 earnings report, gross profit increased by 18% year-over-year, with revenue of $6.11 billion and reported profit of $461.5 million. The results met or exceeded some analysts' expectations, but missed other key metrics. Bitcoin remains Block.com's second-largest revenue source, after its core revenue based on subscriptions and services. XYZ shares fell 3.7% to $70.94 at market close and further declined 9.6% to $64.10 in after-hours trading.