I think PG posted their financing documents: http://ycombinator.com/seriesaa.html http://ycombinator.com/seriesaa.html These were specifically designed for US

I think PG posted their financing documents: http://ycombinator.com/seriesaa.html http://ycombinator.com/seriesaa.html These were specifically designed for US C-corporations. The legalese obviously changes based on the company type [and may not be applicable -- for example, in the case of US LLCs] You will need to start a legal entity, and based on the arrangement you give them a portion of the company ie shares, or some sort of convertible note. Honestly I dont know much about UK companies, so you should start investigating the possible corporate structures.