Microsoft has confirmed that "some new titles" from Bethesda and parent company Zenimax Studios will be "exclusive to Xbox and PC".
There's no qualifier of timed exclusivity here. There's no mention of which games.
"This is the next step in building an industry-leading first party studios team, a commitment we have to our Xbox community," Xbox boss Phil Spencer wrote today in an Xbox Wire post to mark the historic $7.5bn deal being finalised.