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"§ 301.6103(k)(6)-1 Disclosure of return information by certain officers and employees for investigative purposes.
(a) General rule.
(1) Pursuant to the provisions of section 6103(k)(6) and subject to the conditions of this section, an internal revenue employee or an Office of Treasury Inspector General for Tax Administration (TIGTA) employee, in connection with official duties relating to any examination, administrative appeal, collection activity, administrative, civil or criminal investigation, enforcement activity, ruling, negotiated agreement, prefiling activity, or other proceeding or offense under the internal revenue laws or related statutes, or in preparation for any proceeding described in section 6103(h)(2) (or investigation which may result in such a proceeding), may disclose return information, of any taxpayer, to the extent necessary to obtain information relating to such official duties or to accomplish properly any activity connected with such official duties, including, but not limited to --
(i) Establishing or verifying the correctness or completeness of any return or return information;
(ii) Determining the responsibility for filing a return, for making a return if none has been made, or for performing such acts as may be required by law concerning such matters;
(iii) Establishing or verifying the liability (or possible liability) of any person, or the liability (or possible liability) at law or in equity of any transferee or fiduciary of any person, for any tax, penalty, interest, fine, forfeiture, or other imposition or offense under the internal revenue laws or related statutes or the amount thereof for collection;
(iv) Establishing or verifying misconduct (or possible misconduct) or other activity proscribed by the internal revenue laws or related statutes;
(v) Obtaining the services of persons having special knowledge or technical skills (such as, but not limited to, knowledge of particular facts and circumstances relevant to a correct determination of a liability described in paragraph (a)(1)(iii) of this section or skills relating to handwriting analysis, photographic development, sound recording enhancement, or voice identification) or having recognized expertise in matters involving the valuation of property if relevant to proper performance of official duties described in this paragraph;
(vi) Establishing or verifying the financial status or condition and location of the taxpayer against whom collection activity is or may be directed, to locate assets in which the taxpayer has an interest, to ascertain the amount of any liability described in paragraph (a)(1)(iii) of this section for collection, or otherwise to apply the provisions of the Internal Revenue Code relating to establishment of liens against such assets, or levy, seizure, or sale on or of the assets to satisfy any such liability;
(vii) Preparing for any proceeding described in section 6103(h)(2) or conducting an investigation which may result in such a proceeding; or
(viii) Obtaining, verifying, or establishing information concerned with making determinations regarding a taxpayer's liability under the Internal Revenue Code, including, but not limited to, the administrative appeals process and any ruling, negotiated agreement, or prefiling process."