The Internal Revenue Service (IRS) has been lenient in the use of 'square brackets' [ ] when used as notation for a negative number. The 'round brackets' ( ) have always been the standard for showing negative numbers without the use of a 'negative sign' — in filings. It has recently come to our attention that on September 30th, 2025 the service changed numerous internal policies, such as: requirement that all refunds be electronically paid, reduction of allowable deductions and codes for all filings, stricter application of taxpayer-error violations to prepare for future A.I. management, and so on.
NOTE: One of those 'taxpayer-error' violations comes from the use of 'square brackets' instead of 'round brackets'. This can be a common reason for a lawful money return error.