It's been happening for years, although there does seem to have been a lot more recently.
In some cases, it goes full circle. Many years ago, I used to work for Plessey semiconductors. We were bought and sold several times (GEC, Mitel, Zarlink, X-Fab), but several years ago, the Plessey name was back on the building. I left when it was still Mitel, so I'm not fully up to date with what happened after that.
Ian.