BP (NYSE:BP) shares exploded upward after the announcement they had stopped oil from leaking into the Gulf of Mexico.
Shares closed at $38.92, rising $2.74, or 7.57 percent. Share price also continued to move up in trading after close.
In a press conference, BP's Kent Wells was chosen to deliver the news most have been waiting to hear since the the explosion on the Deepwater Horizon oil rig in April started the oil leaking.
BP wasn't sure how long it would take because it wasn't known if the initial closing of the valves would stop the leak, or they've have to continue on with other steps.
Calling it a "critical milestone," Wells did stress that it is not an guaranteed success. Oil could begin flowing again, depending on the results of well-integrity tests, which will search for leaks. That could last up to 48 hours.
Now they also await the first relief well to be completed which will permanently seal the oil well.
BP has said when they stop the oil they wouldn't be producing any more from the well.
The rise in share price brought the market cap of the company up to $121.85 billion.