Each ticket is made up of up to 100 shares, meaning you can buy a 1/100th single share of a ticket for £4.99 up to a full 1/1 share for £249.99.
Here’s an example
If a ticket number wins the El Gordo first prize, then the holder of a full ticket would win £3.5m. A player that holds only a single 1/100th share of that ticket would win 1/100th of the prize - £35,000.