They're not Sheikh Hamdan's, they're Sheikh Maktoum's/Gainsborough Stud's.
It's really weird, because Lammtarra won the '95 Derby in the Green colours of Saeed Maktoum Al Maktoum, but he was running for Godolphin. So it's so hard to work out when the Royal Blues were actually brought in and which horse won the first Group race in them.
That's not hard to work out. Lammtarra was owned by one of the Maktoum's relations and trained by Alex Scott as a 2yo, he won the Washington Singer on debut. Sadly however one of Scott's stable lads murdered him in the Autumn of the 94 season and many of Scott's horses were left in a sort of limbo. Neil Graham took over a few of the horses (Leslie Graham's husband) but Ed Dunlop was then placed in charge of Gainsborough Stables. However a few of the horses were moved to Saeed Bin Suroor, not under the Godollphin banner, one was Lammtarra, who after a setback returned to win the Derby on his seasonal reappearance.