WORKING FOR ESA: INVOICING WITH OR WITHOUT VAT? 
DETAILS AND COMMENTS TO THE QUESTIONS
1                  Are you classified as a taxable person?
For VAT purposes a taxable person is any legal entity (person) - like a company, partnership or an individual - who independently carries out economic activities, i.e. who supplies goods or services in the course of business. Entrepreneurs [dt.: "Unternehmen"] are taxable persons. ESA's contractors are normally all taxable persons, however, (small) university institutes or similar (research) institutions eventually might be not classified as taxable person. How is a taxable person identified?- Taxable persons have a VAT- Identification Number (VAT Reg.No.).  
 
2                  Are you a Prime Contractor to ESA?
The Prime Contractor (or Co-Contractor in case of multiple Primes) is the supplier in direct contractual relationship with ESA. It is the Prime Contractor to invoice ESA directly.
Sub-contractors do not stand in a direct contractual relationship with ESA; they are either paid by the Prime or by ESA, depending on the set-up of the particular contract. Direct payments by ESA to sub-contractors are effected as a service to accelerate payments, however the chosen payment method is of no relevance for VAT matters.
Hence, sub-contractors are to address their invoices to their upper-tier contractor (who may be the Prime or a contractor in between). The relation between a sub-contractor and his upper-tier contractor is, as far VAT is concerned, not influenced by the status of ESA (except for Switzerland as described below).
 
3                  Are you invoicing from an EU-member state?
The identifier is the country in which the invoice issuing taxable person is located. Also as per the EU Invoicing Directive it is required that the invoice mentions the full name and address of both the invoice issuer and the invoice and the invoice recipient (customer).
 
4                  Are you an Italian company?
You are a taxable person located in Italy as per your complete address included on the invoice your are issuing.
 
5                Is your delivery/service supplied within the same country?
For this question the legal address of supplier (invoice issuer) and customer (invoice recipient) mentioned on the invoice is not decisive.
What is relevant is: does the delivery of  a good / the rendering of a service 'cross a border' or is the good/service provided within the country of the supplier?
Example: a delivery of goods from a warehouse in Germany to a location in Germany is a "delivery within the same country", even if the supplier is a Spanish company invoicing their customer a company in France.
 
6                Are you invoicing and supplying from one EU-country to another EU-country?
Only if both the transaction (delivery/service) and the and the invoice (invoice issuer located in a different EU-Member State than addressee of invoice) are 'crossing the border' between two EU Member States  this questions can be answered with "YES". This is then a so-called "intra-Community"-transaction.
 
7                  Is the addressee of your invoice a taxable person?
If the recipient of your invoice is a taxable person, the invoice shall be issued without VAT. How is a taxable person defined?- Taxable persons have a VAT-identification number (VAT Reg.No.). 
 
8                 Is your delivery/service within your country and/or the customer in your country?
Only if you can negate all aspects of this question, your transactions is considered as an export, allowing you to invoice without VAT. This means, both the delivery of goods must be outside your country (or service to a customer outside your country) and your customer has to be outside your country. In practice for ESA-member states this means all services/deliveries of Norwegian or Swiss companies rendered to a place outside their country, this question has to be answered with "No".
 
9                  Is your delivery/service supplied within the same country?
For this question the legal address of supplier (invoice issuer) and customer (invoice recipient) mentioned on the invoice is not decisive.
What is relevant is: does the delivery of  a good / the rendering of a service 'cross a border' or is the good/service provided within the country of the supplier?
Example: a delivery of goods from a warehouse in Germany to a location in Germany is a "delivery within the same country", even if the supplier is a Spanish company invoicing their customer a company in France.
 
11                  Did you receive from ESA an EU VAT exemption form "15/10"?
The EU provides International  Organisations the privilege to be exempted from VAT for intra-community transactions through the EU Council Directive 2006/112/EC, chapter 8 Article 151, 1.b. (published at: http://eur-lex.europa.eu/JOHtml.do?uri=OJ:L:2006:347:SOM:en:HTML). ESA applies this privilege by issuing a VAT EXEMPTION CERTIFICATE for a particular contract or Purchase Order to the Contractor (i.e. the Prime Contractor or the Co-Contractors, not to lower-tier subcontractors).
This certificate is issued by ESA with the authorisation of the national fiscal authority of the country hosting the respective ESA establishment. Currently the Dutch fiscal authorities authorise ESTEC (ESA in the Netherlands), the German fiscal authorities authorise ESOC (ESA in Germany) and the Italian fiscal authorities authorise ESRIN (ESA in Italy).. For the time being ESA’s Headquarter (ESA in France) is not authorized by the French fiscal authorities to issue these exemptions.
By default this VAT-exemption form is issued by ESA at ESTEC, ESOC or ESRIN for all contracts/purchase orders which otherwise would trigger invoices with VAT. The currently used exemption form does not quote the current EU-Directive (2006/112/EC) but it's predecessor 77/388/EEC - Article 15 (10). Nevertheless this form is still valid. Because of the referred old article this exemption certificate often is informally denoted as "15-10 exemption form".
The exemption is valid for all invoices related to the contract/purchase order identified in the certificate.
 
12                  Are you a Dutch company invoicing ESTEC for a service?
Services provided by Dutch taxable persons (companies) to ESTEC, invoicing ESTEC, are exempted.