Wikimedia UK v1.0/Wikimedia and UK charity law
This is not to say that Wikipedia/Wikimedia is covered by UK charity law as it stands. However with the talk of setting up national chapters the following may be useful/interesting. The following refers to charity law in England and Wales, as Scotland is different.
(IANAL of course, but compliance with charity law is part of my day job Secretlondon.)
Wikipedia would count as charitable under the head of "the advancement of education". However organisations "raising funds for other charities where the organisers do not have any say over how the funds are spent"  are not charitable.
The regulator of charities in England and Wales is the Charity Commission Charity Commission. It is obligatory to register if you have an annual income of over £1,000. If we had an annual income of less than £5,000 we would count as a "small charity" (that figure may now be £10,000).
Details on how to register are found here: CC21 - Registering as a Charity
From Charities Working Internationally:
8. When considering whether an organisation which plans to work internationally is charitable, we first look at whether it would be charitable to carry out those objects in England and Wales. If it would, we then look at whether the organisation is set up for the benefit of the public.
9. Public benefit, unless it is self-evident, has to be demonstrated by every organisation seeking recognition as a charity. The existence of public benefit is more likely to be treated as self-evident where the object is to relieve poverty, advance education or promote religion. We test the public benefit issue in the same way for organisations intending to operate in whole or in part in other countries as we do for organisations operating in England and Wales. See RR8 "The Public Character of Charities" for more information on public benefit generally. RR1a "Recognising New Charitable Purposes" gives more information on how we approach the public benefit issue in the context of new charitable purposes.
10. The courts have said that to have an object of changing the law or policy of a foreign government is not for the benefit of the public. For more information about political objects and activities, see CC9 "Political Activities and Campaigning by Charities".
11. There are some purposes to be carried out in other countries which are not charitable because they are contrary to public policy. For example, purposes whose effect would be to damage this country’s relations with a friendly State, or to undermine our national security, would not be charitable. We would look at each case of this type on an individual basis.
Can charities be set up to support an organisation outside the United Kingdom?Edit
14. If an organisation is set up to raise funds for a specified organisation in another country, it may or may not be charitable.
15. A common example might be where an organisation has been set up to support the work of a particular hospital located overseas. The deciding factor will be the degree of control the trustees have over the use of the funds passed to the hospital.
- Are merely required to pass over any funds collected to the hospital; and
- Have no say in how those funds are to be used,
then the organisation is merely acting as a channel for the funds and is not charitable. The organisation could not ensure in these circumstances that the hospital would use the funds only for purposes which were regarded as charitable in accordance with the laws of England and Wales.
16. If such an organisation wishes to be a charity it should clearly demonstrate that:
- It has purely charitable objects;
- Its trustees have control over how its funds will be used; and
- The trustees are responsible for the selection of beneficiaries and/or projects to support.
17. Careful consideration should be given to the drafting of objects. For example, an object that states simply that the organisation is established to "support the charitable work of the hospital" would not be ideal. If the hospital ever closed, the supporting body would have no outlet for its funds. In such cases, if the supporting body is a charity, the Commission’s intervention may be required if its work is to carry on. It would be preferable for the objects to be expressed in a broader way, for example "The relief of sickness in [country] in particular by supporting the charitable work of the hospital."
This wording would provide a potentially wider outlet for the organisation’s funds.
18. The hospital can suggest the types of support it requires so that funds can be directed where they are most needed, but the final decision about how funds will be used must rest with the trustees of the supporting charity.