Yes, but it's more like a "joint venture" with a lot of money involved.
I don't think it is an actual "buy in" into the RE company.
I haven't read exactly what they plan to do, but I would surmise that Polaris wish to work with RE in getting the Victory motorcycles distributed in India, and perhaps even be made there.
I suppose it's possible that there could even be some name-swapping between these brands, or even some joint bikes being made. Part Victory and part Royal Enfield.
Who knows?
I did read one unsubstantiated comment on the web that RE has abandoned their twin-cylinder effort, and perhaps if that is correct, this joint venture might have something to do with that. Maybe they want to make a V-Twin Royal Enfield with a Victory V-Twin engine in it?
We'll have to wait until more info is available to know for sure what's going on.