This was confirmed a couple of months ago, but the report from The Wall Street Journal has revealed more details, such as how much this move could potentially cost Disney in terms of licensing revenue, which is said to be as much as $300 million. However we suppose it is possible that they could make up for it with their subscribers.
As for the existing Marvel shows produced by Netflix for their platform, the good news is that Disney will not be taking those away from Netflix. A tweet by Ben Fritz who reports for The Wall Street Journal has confirmed that those Netflix-produced Marvel TV series will remain on Netflix, along with future seasons and off-shoots.
To answer the same question from a few people: The Marvel shows currently on Netflix, and any spin-offs from them, will stay on that platform
— Ben Fritz (@benfritz) November 9, 2017
When Disney announced their plans to launch their own streaming platform, Netflix had stated that they were hoping to work out some kind of deal that would allow them to keep Marvel and Lucasfilm content past 2019. Whether or not that will happen remains to be seen, but for now it looks like Disney plans on keeping its content to itself.