Let be a smooth cubic fourfold over and let , with , be the Lagrangian fibration whose fibres are the smooth hyperplane sections , with . There always exists a (not unique) smooth compactification which is a hyper-Kälher manifold of OG10 type. Since two different compactifications are birationally equivalent their Chow motives are isomorphic. For a general a geometrical construction of a smooth compactification with irreducible fibres has been described in [LSV]. In this note we prove that the Chow motive is a direct summand of the (twisted) motive of and therefore is is of abelian type if is of abelian type.We describe a 10 -dimensional family of cubics such that the compactification is unique, smooth, with irreducible fibres, and the Chow motive is of abelian type.

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