May 9 (Reuters) - Apollo-backed Concord on Thursday said

it will not raise its $1.25 per share offer for Hipgnosis Songs

Fund ( HPGSF ) days after Blackstone outbid it for the

owner of music rights of artists, including Shakira and Blondie.

Blackstone sweetened its offer to $1.30 apiece or about

$1.57 billion in April, above Concord's bid and had won

Hipgnosis's board backing for the deal.