Every director must, during his whole term of service, be a citizen of the United States, and at least a majority of the directors must have resided in the State, Territory, or District in which the association is located, or within one hundred miles of the location of the office of the association, for at least one year immediately preceding their election, and must be residents of such State or within one-hundred-mile territory of the location of the association during their continuance in office, except that the Comptroller may, in the discretion of the Comptroller, waive the requirement of residency, and waive the requirement of citizenship in the case of not more than a minority of the total number of directors. Every director must own in his or her own right either shares of the capital stock of the association of which he or she is a director the aggregate par value of which is not less than $1,000, or an equivalent interest, as determined by the Comptroller of the Currency, in any company which has control over such association within the meaning of section 1841 of this title. If the capital of the bank does not exceed $25,000, every director must own in his or her own right either shares of such capital stock the aggregate par value of which is not less than $500, or an equivalent interest, as determined by the Comptroller of the Currency, in any company which has control over such association within the meaning of section 1841 of this title. Any director who ceases to be the owner of the required number of shares of the stock, or who becomes in any other manner disqualified, shall thereby vacate his place.