What is the ruling on paying a subscription fee to participate in a horse racing competition with a mare?

There is no objection to paying subscription fees for competitions if they are in exchange for services provided to the competitors, or if they are a prize for the winner. The jurists have agreed on the permissibility of offering compensation in horse, camel, and archery races, if the compensation is from one of the competitors or from an outsider, based on the Prophet's (peace and blessings be upon him) saying: "There is no prize except in archery, hoofed animals (horses and camels), or a hoof."