How long should a foundation keep grantee reports?

Are there legal requirements, IRS or other, for foundations regarding receiving and retaining paperwork from grantees that documents how grant dollars were spent?

A good rule of thumb is to keep grant materials for seven years. We suggest four years at a minimum. The IRS audit statute of limitations is three years. So, it is important to keep grant materials around that long just in case you get audited. In some areas we suggest seven years because the statute of limitations on fraud is six years.