With respect to the recently added checkbox for Qualifying Insurance Corporations (see the Reminders section below for details), a new attachment requirement has been added to the instructions for that election. See new item number 3 under How to make the election under the instructions for Election To Be Treated as a Qualifying Insurance Corporation.
With respect to certain amounts on Form 8621 that are reported on income tax returns, some of the references to Form 1040 (on pages 10 through 13 of these instructions) had to be updated to reflect further redesign of Form 1040 for tax year 2019.
The line 16f instructions were modified to update the Revenue Ruling for the rates for interest determined under section 6621.
Form 8621 & Instructions
For the latest information about developments relating to Form 8621, and its instructions, such as legislation enacted after they were published, go to www.irs.gov/form8621.