i would've said to email them, but the link you provided is a domain for sale.
anyway, if a company wants to be supplied something, they go to the source. who could possibly be generating balance sheets for a "global stock". well, the company that issued that global stock. The data provider takes the financial data from the source (paid or by some other deal) and puts it on display to their own (possibly wider) audience.
as for trading data, stock exchanges have to track all that info, so the data provider, you guessed it, once again goes to the source for that dataset (paid or by other deals, possibly with some telecom intermediary that has ties to multiple international stock exchanges) and re-distributes it.
it wouldn't be hard for a site to replicate financial data from another site that's online though, using some sort of automated macro API that copies and pastes.