Use this form to figure the increase in tax for the recapture of investment credit claimed and for the recapture of a qualifying therapeutic discovery project grant. Current Revision Form 4255 PDF Instructions for Form 4255 (Print Version PDF) Recent Developments None at this time. Other Items You May Find Useful All Revisions for Form 4255 Notice 2009-23, Qualifying Gasification Project Program Notice 2009-24, Qualifying Advanced Coal Project Program Notice 2011-24, Guidance for Phase II of the Qualifying Advanced Coal Program Under Section 48A and the Qualifying Gasification Program Under Section 48B Other Current Products Related About Form 1041, U.S. Income Tax Return for Estates and Trusts About Form 1065, U.S. Return of Partnership Income About Form 1120, U.S. Corporation Income Tax Return About Form 1120-S, U.S. Income Tax Return for an S Corporation About Form 3468, Investment Credit