Source: http://legalarium.com/cfr/195.html
Timestamp: 2019-04-21 17:00:41+00:00

Document:
Sec. 2.195. Receipt of trademark correspondence.
(1) The Office is not open for the filing of correspondence on any day that is a Saturday, Sunday, or Federal holiday within the District of Columbia. Except for correspondence transmitted electronically under paragraph (a)(2) of this section or transmitted by facsimile under paragraph (a)(3) of this section, no correspondence is received in the Office on Saturdays, Sundays, or Federal holidays within the District of Columbia.
(2) Trademark-related correspondence transmitted electronically will be given a filing date as of the date on which the Office receives the transmission.
(3) Correspondence transmitted by facsimile will be given a filing date as of the date on which the complete transmission is received in the Office unless that date is a Saturday, Sunday, or Federal holiday within the District of Columbia, in which case the filing date will be the next succeeding day that is not a Saturday, Sunday, or Federal holiday within the District of Columbia.
(4) Correspondence filed in accordance with §2.198 will be given a filing date as of the date of deposit as “Express Mail” with the United States Postal Service.
(b) Correspondence delivered by hand . Correspondence may be delivered by hand during hours the Office is open to receive correspondence.
(c) Facsimile transmission. Except in the cases enumerated in paragraph (d) of this section, correspondence, including authorizations to charge a deposit account, may be transmitted by facsimile. The receipt date accorded to the correspondence will be the date on which the complete transmission is received in the Office, unless that date is a Saturday, Sunday, or Federal holiday within the District of Columbia. See §2.196. To facilitate proper processing, each transmission session should be limited to correspondence to be filed in a single application, registration or proceeding before the Office. The application serial number, registration number, or proceeding number should be entered as a part of the sender's identification on a facsimile cover sheet.
(5) Madrid-related correspondence submitted under §7.11, §7.21, §7.14, §7.23, §7.24, or §7.31 of this title.
(e) Interruptions in U.S. Postal Service.
(1) If the Director designates a postal service interruption or emergency within the meaning of 35 U.S.C. 21(a), any person attempting to file correspondence by “Express Mail Post Office to Addressee” service who was unable to deposit the correspondence with the United States Postal Service due to the interruption or emergency may petition the Director to consider such correspondence as filed on a particular date in the Office.
(iii) Include a statement that the correspondence would have been deposited with the United States Postal Service on the requested filing date but for the designated interruption or emergency in ”Express Mail” service; and that the correspondence attached to the petition is the original correspondence or a true copy of the correspondence originally attempted to be deposited as Express Mail on the requested filing date.
(3) Paragraphs (e)(1) and (e)(2) of this section do not apply to correspondence that is excluded from the Express Mail procedure pursuant to §2.198(a)(1).

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