Groupe Eurotunnel SA being a French company with shares which, unlike a UK company, are not represented by share certificates, in order for its shares to be tradable in the UK, they have to be represented by an instrument which is recognised.  This is the Crest Depository Interest (CDI).  CDIs are issued through CREST (now Euroclear UK & Ireland).
 
Only CREST participants can have an account with CREST. CREST participants are broadly financial intermediaries not individuals. Therefore, as a general rule, individuals will hold their CDIs through an intermediary: a broker, a bank or a nominee.

All the shares represented by the CDIs issued through CREST in the UK are held by an intermediary, SIS, which is the registered shareholder on behalf of all CDI holders.  In order for any transaction affecting the shares to take place, instructions (and funds, where payment is required) need to go from the ultimate CDI holder, through its own intermediary (bank, broker or nominee) to CREST and then to SIS. 

This chain means that whatever deadline is imposed on shareholders, the deadline for ultimate CDI holders will be shortened by at least two days: one for CREST to give instructions to SIS and one for CREST participants to give instructions to CREST. The time given by CREST participants to the ultimate CDI holders may vary. 

Computershare is one such nominee which, in order to facilitate the transition from being shareholders in TNU to supporting the new Groupe Eurotunnel, was set up by Eurotunnel for its retail investors. 

Computershare is neither a broker nor a bank.  Therefore, unlike holding CDIs through a broker or a bank where an account is in place, transactions involving payment through Computershare require cheques to clear before Computershare can pass on CDI holders’ instructions.  In the UK, it takes three days for a cheque to clear.

Any transactions where CDI holders may wish to sell or purchase additional shares can only be carried out by a broker or a bank not by Computershare.

In order to avoid the effect of the time constraints of going through CREST, UK holders may chose to register directly as shareholders with Groupe Eurotunnel’s registrars in France BNP Securities Services (an option given at the time of the Exchange Offer).