N.H. Rev. Stat. Ann. § 383-A:4-403

For the purpose of strengthening its financial condition, subject to the approval of its board of directors, a state bank may receive contributions to its capital funds and in consideration for those funds may issue capital debentures to any person. The board of directors may not issue the capital debentures unless (i) it files an application for approval of the issuance of the capital debenture under RSA 383-A:6-602 specifying the principal amount of capital debentures which it proposes to issue, the terms and conditions of the debentures including interest rate and retirement provisions, the name of any bank or other persons proposing to purchase capital debentures, the principal amount of debentures which it proposes to purchase, and its reasons for issuing those debentures, and (ii) is permitted to issue the debentures by the commissioner. Capital debenture shall be considered legal investments for any person named in the plan. Capital debentures may be retired only from earnings unless otherwise authorized by the commissioner.