1 722 Injunction to restrain assessment . R.S.,sec . 3224, p. 619 . U.S.C.,p.1193. Exceptions to re- str ict ion s . Waivers . Errors . Jeopardy assess- ments, p . 1723 . Bankruptcy, etc ., p ° 1725 . Assessment, etc ., of defici ency . Vol.44,p.109 . Collection of defi- ciency found by Board . Payment on demand if petition not filed . Waiver of restric- tions by taxpayer. Increase of deficiency after notice mailed . Condition . Restriction on de- termining deficiency after notice . Exceptions . Post, p. 1723 . Mathematical error, not a notice of defi- ciency. Cr edits or ref unds . Post, p. 1731 . 74T H C ONGRESS . SESS . II. CH. 690. JUNE 22, 1936. become final . Notwithstanding the provisions of section 3224 of the Revised Statutes the making of such assessment or the beginning of such proceeding or distraint during the time such prohibition is in force may be enjoined by a proceeding in the proper court . For exceptions to the restrictions imposed by this subsection, see- (1) Subsection (d) of this section, relating to waivers by the taxpayer ; (2) Subsection (f) of this section, relating to notifications of mathe matical e rrors app earing up on the fac e of the return ; (3) Section 273, relating to jeopardy assessments ; (4) Section 274, relating to bankruptcy and receiverships ; and (5) Section 1001 of the Revenue Act of 1926, as amended, relat- ing to assessment or collection of the amount of the deficiency determined by the Board pending court review. (b) COLLECT ION OF DEF ICIENCY FO UND BY B O A RD .-If the tax paye r fi les a p etit ion with the Bo ard, the ent ire amo unt rede term ined as the deficiency by the decision of the Board which has become final shall be assessed and shall be paid upon notice and demand from the col- lector . No part of the amount determined asa deficiency by the Commissioner but disallowed as such by the decision of the Board which has become final shall be assessed or be collected by distraint or by proceeding in court with or without assessment . (c) FAILURE TO FILE PETITION .-If the taxpayer does not file a petition with the Board within the time prescribed in subsection (a) of this section, the deficiency, notice of which has been mailed to the taxpayer, shall be assessed, and shall be paid upon notice and demand from the collector . (d) WAIVER OF RESTRICTIONS.-The taxpayer shall at any ti me have the right, by a signed notice in writing filed with the Commis- sioner, to waive the restrictions provided in subsection (a) of this section on the assessment and collection of the whole or any part of th e defici ency . (e) I NCRE ASE OF D EFIC IENCY AFT ER N OTICE MAILED.-The Board sh all have jurisdict ion to re determine the corr ect amount of the deficiency even if the amount so redetermined is greater than the amount of the deficiency, notice of which has been mailed to the taxpayer, and to determine whether any penalty, additional amount or addition to the tax should be assessed-if claim therefor is asserted by the Commissioner at or before the hearing or a rehearing . (f) FU RTHER DE FICI ENCY LETTER S RESTRICTED.-If the Commis- sioner has mailed to the taxpayer notice of a deficiency as provided in subsection (a) of this section, and the taxpayer files a petition with t he B oard wit hin the time pre scri bed in s uch subs ecti on, the Com- missioner shall have no right to determine any additional deficiency in respect of the same taxable year, except in the case of fraud, and except as provided in subsection (e) of this section, relating to assertion of greater deficiencies before the Board, or in section 273 (c), relating to the making of jeopardy assessments . If the tax- payer is notified that, on account of a mathematical error appearing upon the face of the return, an amount of tax in excess of that shown upon the return is due, and that an assessment of the tax has been or will be made on the basis of what would have been the correct amount of tax but for the mathematical error, such notice shall not be considered (for the purposes of this subsection, or of subsection (a) o f this se ction, p rohibiti ng asses sment an d collec tion unti l notice of deficiency has been mailed, or of section 322 (c), prohibiting credits or refunds after petition to the Board of Tax Appeals) asa notice of a deficiency, and the taxpayer shall have no right to file a petition with the Board based on such notice, nor shall such assess-
