26 USC 6679 - Failure to file returns, etc., with respect to foreign corporations or foreign partnerships

(a) Civil penalty 

(1) In general 
In addition to any criminal penalty provided by law, any person required to file a return under section[1] 6046 and 6046A who fails to file such return at the time provided in such section, or who files a return which does not show the information required pursuant to such section, shall pay a penalty of $10,000, unless it is shown that such failure is due to reasonable cause.
(2) Increase in penalty where failure continues after notification 
If any failure described in paragraph (1) continues for more than 90 days after the day on which the Secretary mails notice of such failure to the United States person, such person shall pay a penalty (in addition to the amount required under paragraph (1)) of $10,000 for each 30-day period (or fraction thereof) during which such failure continues after the expiration of such 90-day period. The increase in any penalty under this paragraph shall not exceed $50,000.
(b) Deficiency procedures not to apply 
Subchapter B of chapter 63 (relating to deficiency procedure for income, estate, gift, and certain excise taxes) shall not apply in respect of the assessment or collection of any penalty imposed by subsection (a).
[1] So in original. Probably should be “sections”.