ILC is established as a UK company limited by guarantee. This is a long established and common legal form in the UK for not for profit entities such as membership organisations.
It is a company and therefore has a separate legal identity to its members. It can therefore contract and undertake transactions in its own name, rather than in that of its members.
The members benefit from limited liability, i.e. they are not personally liable for any debts of the company beyond the amount they have guaranteed which is £1. The difference between this and a typical trading company is that the members do not contribute in advance, in the form of capital, but only on liquidation if there is a deficit of assets over liabilities. In such a case the liability of each member is limited to the amount they have guaranteed, £1. Hence the term ‘limited by guarantee’. Also, the term used is members rather than shareholders.
The Company’s registered address and Company registration number can be found on this link.