29 C.F.R. § 102.48 : Labor — REGULATIONS RELATING TO LABOR — NATIONAL LABOR RELATIONS BOARD — RULES AND REGULATIONS, SERIES 8 — PROCEDURE UNDER SECTION 10(A) TO (I) OF THE ACT FOR THE PREVENTION OF UNFAIR LABOR PRACTICES — No exceptions filed; exceptions filed; motions for reconsideration, rehearing, or reopening the record

(a) No exceptions filed. If no timely or proper exceptions are filed, the findings, conclusions, and recommendations contained in the Administrative Law Judge's decision will, pursuant to Section 10(c) of the Act, automatically become the decision and order of the Board and become its findings, conclusions, and order, and all objections and exceptions must be deemed waived for all purposes.
(b) Exceptions filed.
(1) Upon the filing of timely and proper exceptions, and any cross-exceptions or answering briefs, as provided in §102.46, the Board may decide the matter upon the record, or after oral argument, or may reopen the record and receive further evidence before a Board Member or other Board agent or agency, or otherwise dispose of the case.
(2) Where exception is taken to a factual finding of the Administrative Law Judge, the Board, in determining whether the finding is contrary to a preponderance of the evidence, may limit its consideration to such portions of the record as are specified in the exceptions, the supporting brief, and the answering brief.
(c) Motions for reconsideration, rehearing, or reopening the record. A party to a proceeding before the Board may, because of extraordinary circumstances, move for reconsideration, rehearing, or reopening of the record after the Board decision or order.
(1) A motion for reconsideration must state with particularity the material error claimed and with respect to any finding of material fact, must specify the page of the record relied on. A motion for rehearing must specify the error alleged to require a hearing de novo and the prejudice to the movant from the error. A motion to reopen the record must state briefly the additional evidence sought to be adduced, why it was not presented previously, and that, if adduced and credited, it would require a different result. Only newly discovered evidence, evidence which has become available only since the close of the hearing, or evidence which the Board believes may have been taken at the hearing will be taken at any further hearing.
(2) Any motion pursuant to this section must be filed within 28 days, or such further period as the Board may allow, after the service of the Board's decision or order, except that a motion to reopen the record must be filed promptly on discovery of the evidence to be adduced.
(3) The filing and pendency of a motion under this provision will not stay the effectiveness of the action of the Board unless so ordered. A motion for reconsideration or rehearing need not be filed to exhaust administrative remedies.

29 C.F.R. §102.48

28 FR 7974, 8/6/1963, as amended at 34 FR 14432, 9/16/1969; 51 FR 23746, 7/1/1986; 56 FR 49143, 9/27/1991; 82 FR 11754, 3/6/2017