Section 10.63 - Service of complaint; service of other papers; service of evidence in support of complaint; filing of papers(a)Service of complaint -(1)In general. The complaint or a copy of the complaint must be served on the respondent by any manner described in paragraphs (a)(2) or (3) of this section.(2)Service by certified or first class mail.(i) Service of the complaint may be made on the respondent by mailing the complaint by certified mail to the last known address (as determined under section 6212 of the Internal Revenue Code and the regulations thereunder) of the respondent. Where service is by certified mail, the returned post office receipt duly signed by the respondent will be proof of service.(ii) If the certified mail is not claimed or accepted by the respondent, or is returned undelivered, service may be made on the respondent, by mailing the complaint to the respondent by first class mail. Service by this method will be considered complete upon mailing, provided the complaint is addressed to the respondent at the respondent's last known address as determined under section 6212 of the Internal Revenue Code and the regulations thereunder.(3)Service by other than certified or first class mail.(i) Service of the complaint may be made on the respondent by delivery by a private delivery service designated pursuant to section 7502(f) of the Internal Revenue Code to the last known address (as determined under section 6212 of the Internal Revenue Code and the regulations thereunder) of the respondent. Service by this method will be considered complete, provided the complaint is addressed to the respondent at the respondent's last known address as determined under section 6212 of the Internal Revenue Code and the regulations thereunder.(ii) Service of the complaint may be made in person on, or by leaving the complaint at the office or place of business of, the respondent. Service by this method will be considered complete and proof of service will be a written statement, sworn or affirmed by the person who served the complaint, identifying the manner of service, including the recipient, relationship of recipient to respondent, place, date and time of service.(iii) Service may be made by any other means agreed to by the respondent. Proof of service will be a written statement, sworn or affirmed by the person who served the complaint, identifying the manner of service, including the recipient, relationship of recipient to respondent, place, date and time of service.(4) For purposes of this section, respondent means the practitioner, employer, firm or other entity, or appraiser named in the complaint or any other person having the authority to accept mail on behalf of the practitioner, employer, firm or other entity, or appraiser.(b)Service of papers other than complaint. Any paper other than the complaint may be served on the respondent, or his or her authorized representative under § 10.69(a)(2) by:(1) Mailing the paper by first class mail to the last known address (as determined under section 6212 of the Internal Revenue Code and the regulations thereunder) of the respondent or the respondent's authorized representative,(2) Delivery by a private delivery service designated pursuant to section 7502(f) of the Internal Revenue Code to the last known address (as determined under section 6212 of the Internal Revenue Code and the regulations thereunder) of the respondent or the respondent's authorized representative, or(3) As provided in paragraphs (a)(3)(ii) and (a)(3)(iii) of this section.(c)Service of papers on the Internal Revenue Service. Whenever a paper is required or permitted to be served on the Internal Revenue Service in connection with a proceeding under this part, the paper will be served on the Internal Revenue Service's authorized representative under § 10.69(a)(1) at the address designated in the complaint, or at an address provided in a notice of appearance. If no address is designated in the complaint or provided in a notice of appearance, service will be made on the office(s) established to enforce this part under the authority of § 10.1 , Internal Revenue Service, 1111 Constitution Avenue, NW., Washington, DC 20224.(d)Service of evidence in support of complaint. Within 10 days of serving the complaint, copies of the evidence in support of the complaint must be served on the respondent in any manner described in paragraphs (a)(2) and (3) of this section.(e)Filing of papers. Whenever the filing of a paper is required or permitted in connection with a proceeding under this part, the original paper, plus one additional copy, must be filed with the Administrative Law Judge at the address specified in the complaint or at an address otherwise specified by the Administrative Law Judge. All papers filed in connection with a proceeding under this part must be served on the other party, unless the Administrative Law Judge directs otherwise. A certificate evidencing such must be attached to the original paper filed with the Administrative Law Judge.(f)Effective/applicability date. This section is applicable beginning August 2, 2011.T.D. 9011, 67 FR 48765 , July 26, 2002, as amended by T.D. 9359, 72 FR 54544 , 54552, Sept. 26, 2007; T.D. 9527, 76 FR 32309 , June 3, 2011