According to Article 7 of the Credit Card Charter of China Merchants Bank (Ninth Edition):
China residents who have reached the age of 18 and have full capacity for civil conduct and good credit standing, foreigners with full capacity for civil conduct and compatriots from Hong Kong, Macao and Taiwan with full capacity for civil conduct can apply for personal credit card master cards with their valid identity documents.
Personal cardholders can also apply for supplementary cards for specific natural persons with full civil capacity or natural persons with limited civil capacity. Supplementary card application materials must be confirmed by the main card holder by personal signature, customer service telephone recording, electronic signature or the way recognized by both the cardholder and the card issuer. The main cardholder can apply for cancellation of the supplementary card at any time.
Extended data:
According to Article 11 of the Credit Card Charter of China Merchants Bank (Ninth Edition):
After receiving the credit card, the cardholder shall immediately sign the same signature as the application form in the signature column on the back of the credit card, and use the same signature when using the credit card transaction, otherwise the losses arising therefrom shall be borne by the cardholder, unless otherwise agreed between the cardholder and the card issuing institution or stipulated by the accepting institution or bank card organization.
Some specially designed cards don't need to be signed on the back of the credit card, but they can be used normally after a password is set. The cardholder can set the password through the channel designated by the card issuer.
China Merchants Bank-Credit Card Articles of Association of China Merchants Bank (9th Edition)