NIH just released information concerning the "Standard Terms of Award" for grants funded with ARRA "Stimulus" funds. These are the standardized terms that control how instutitions can use the funds they are awarded pursuant to grant applications. For those who give a shit, some details are inside the crack.
Importantly, it appears that--like regular NIH awards--ARRA awards will (1) allow carryover from one non-competitive segment to the next and (2) one-year no-cost extensions. The former means that if you have a two-year award and you fail to use your entire first year's budgeted funds during the first year, you can just go ahead and carry the unused balance into the second year, rather than having to return it to NIH. The latter means that if by the end of the two-year award you have not spent the entire budget, you will be permitted to extend the term of the award by another year in order to allow for the remaining funds to be spent, rather than returned to NIH.
Given the purpose of the ARRA--to "stimulate" the economy--and all of the public pronouncements by the administration that use of these funds was going to be subject to a lot of oversight to be sure that purpose is fulfilled, some of us have been concerned that ARRA awards would not allow this kind of usual budgetary flexibility. Given the unpredictability of scientific research, this news is a tremendous relief to PIs, departmental business managers, and institutional grants administrators.
One thing that *is* going to be a budgetary restriction that isn't ordinarily imposed, however, is that funds *cannot* be reallocated from a parent grant to an ARRA-funded supplement, or vice versa.