If you are required to file
Form 5472 and you either fail to file or file a substantially incomplete return, the
IRS could apply a penalty of $10,000 USD per year. Your company will also be under greater scrutiny from the IRS with possible audits and follow-ups in subsequent years.
Other sources have noted that, while the form instructions state that the penalty is $10,000, the Tax Cuts and Jobs Act recently increased the applicable penalty in Section 6038A(d)(1) from $10,000 to $25,000 beginning in 2018.