QUESTIONNAIRE
of the Chairman (Member) of the Executive Body, Supervisory Council of the legal entity shareholder which intends to acquire or increase a substantial share in the bank

Насколько я понял, запятая между Executive Body и Supervisory Council выполняет роль "или", то есть группировка такая:

QUESTIONNAIRE
(of the Chairman Member of the (Executive Body or Supervisory Council)) of the legal entity

Я прав?