Complex sentence: In 2008, it was acquired by Robert Trujillo, bassist with Metallica, who agreed in writing to relinquish the instrument to the family at any time for the same purchase price.
Split into simpler sentences: In 2008, it was subsequently acquired by Robert Trujillo, bassist with Metallica. Although Trujillo currently owns the instrument, the Metallica bassist agreed in writing to relinquish the instrument to the family at any time for the same purchase price.