Yes, a signature on each EC declaration of conformity is mandatory. However, it does not necessary have to be signed by hand, particularly with series manufacture of products with very large quantities. According to the European machinery committee, all that is necessary is for the EC declaration of conformity to be "signed by a person whose signature is binding for the manufacturer or his authorised representative established in the Community". What's important in this context is that the declaration of conformity produced with a machine signature must be very difficult to forge.