That's because the LS and S-Type share the same underpinnings.I think MN12 development predates Ford's involvement with Jaguar, but they benchmarked against the BMW 6-Series I think.
That said, when you look at the suspension of a Lincoln LS/Jaguar S-Type, it does look quite similar.
And yup, the MN12 had its sights set firmly on the BMW 6 Series. Coilovers and a multilink suspension on an American touring coupe? They didn't get that idea from Detroit in 1989.