It has been possible to claim the I.R.C. § 121 exclusion ($250,000 on a separate return, $500,000 on a joint return) in conjunction with the involuntary conversion provision. But authority has been lacking for using an I.R.C. § 121 exclusion along with like-kind exchange treatment. In late January, 2005, the Internal Revenue Service published guidance for doing precisely that – coupling the Section 121 exclusion with like-kind exchange procedures. The guidance is effective January 27, 2005 but taxpayers may apply the rules in taxable years for which the period of limitation has not expired.