The Bill & Melinda Gates Foundation states very clearly on its website what it will not fund. It does not give grants or donations to individuals and it will not accept unsolicited proposals. Instead the staff at The Foundation proactively identifies the organisations (that must be US tax exempt) that fall within their areas of interest. In addition, the Foundation will not support projects addressing health problems in developed countries, it will not support political campaigns and legislative lobbying efforts, building or capital projects nor projects that exclusively serve a religious purpose (see www.gatesfoundation.org)
In contrast, another very large US Foundation, the William and Flora Hewlett Foundation, does accept unsolicited applications and does not set any deadlines for these types of applications, although it warns that the success rate for unsolicited applications are low. It indicates on its website that it will support general operating support for an organisation rather than project support and it will also provide grants to “develop the organisational health and efficiency of [its] grantees”. (see www.hewlett.org)