By now almost everyone knows that most of the so-called "Bush tax cuts" provisions will expire at the end of 2012, but there are 53 tax breaks that officially expired on January 1, 2012, including:

• The expanded exemption amounts for the Alternative Minimum Tax (AMT), also referred to as the "AMT patch", which protects approximately 30 million middle-class taxpayers from the AMT, at a cost of $70 billion a year;
• The research and development tax credit;
• 100% bonus depreciation;
• 100% expensing under section 179 of the Internal Revenue Code

See the attached here for a complete list of the 53 expiring tax breaks in a list compiled by the Joint Committee on Taxation for expiring tax provisions in the years 2010 through 2020.

Of course, as has been the case in the past, Congress is expected to revive a number of these provisions, and, since this is an election year, it will probably happen later rather than sooner, after the usual political wrangling. A case in point is the two month extension of the payroll tax cut, which was scheduled to expire on January 1, 2012, but was extended for two months at the eleventh hour, only because it affected payrolls beginning January 1 and action had to be taken to prevent the chaos of a retroactive change.