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HMRC internal manual

VAT Cost Sharing Exemption Manual

How the condition are to be interpreted: Independent Group of Persons: Must the CSG be separate from its members?

Yes. The CSG must be a separate taxable person from its members in order to be able to make exempt supplies for VAT purposes to its members. It must therefore be able to take a legal form that is capable of being a taxable person that can be registered for VAT if it were making taxable supplies, that is, it is capable of meeting the VAT registration criteria or would be if it were not wholly engaged in making exempt supplies.

Subject to the above considerations the CSG can take whatever legal form its members decide.

See V1- 28, Registration for the types of entity that would qualify.