Id like to see the small print. But id hazard a guess at 9 years old as the 4th owner, chances of you getting a new battery for "free" are zero.No idea, but the insurers wouldn't cover it if they didn't have confidence in the lifespan of the battery.
You may well get the actual component for free, but it will be dependant on dealer servicing from new, stamped service book, diagnosis by them of the fault, at your cost, and cost to swap out will be yours too. Or something like this.
Whatever the details, the chances of you rocking up for a free battery pack at 9 years as a subsequent owner are slim.
Ford wriggle out of their body warranty because the inspection page in the service book isnt stamped. Because their dealers generally dont stamp it, and no one notices untill its too late.
The motor industry are well versed in avoiding such warranty headaches.