A private foundation that makes a grant to another organization must either verify the status of the potential grantee as a permitted public charity or exercise expenditure responsibility with respect to the grant to avoid making a taxable expenditure under Section 4945. Treasury regulations promulgated under Section 170 and Section 509 identify the information on which a private foundation or other contributor is permitted to rely for purposes of determining whether a potential grantee is a permitted public charity. These regulations were updated in 2011 as a result of changes to the method of calculating public support that were implemented as part of the Pension Protection Act of 2006. Generally speaking, the changes included the use of the organization’s normal method of accounting to calculate the test (rather than the mandatory use of the cash method) and the use of five years of data (rather than only four). The specific change that is the focus of the discussion below is the elimination of a special provision colloquially known as the “tipping rules,” which caused an organization to lose its public charity tax status suddenly and unexpectedly if it received a significant contribution from a single donor.