The decision by the Court of Cassation adds a further twist to a long-running case whose initial handling was sharply criticised by independent forensic experts.
Prosecutors accused Amanda Knox and her ex-boyfriend Raffaele Sollecito of assaulting and killing Kercher in 2007.
They were initially found guilty and sentenced to 26 and 25 years in prison respectively.
In 2011, their convictions were overturned and they were released after serving four years.
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The teen was stabbed as she slept in her bed in the West Bank in Israel.
Transgender US service members will be able to serve openly and cannot be discharged on the basis of their gender identity.
Singer Rita Ora has been hospitalised after reportedly suffering from exhaustion just hours after the man who burgled her home was jailed.