A private foundation is a legal entity set up by an individual, a family or a group of individuals, for a purpose such as philanthropy or other legal economic object. The Bill & Melinda Gates Foundation is the largest private foundation in the U.S. with over $38 billion in assets. However, most private foundations are much smaller. Approximately two-thirds of the more than 84,000 foundations which file with the IRS, in 2008, have less than $1 million in assets, and 93% have less than $10 million in assets. In aggregate, private foundations in the U.S. control over $628 billion in assets and made more than $44 billion in charitable contributions in 2007.
Unlike a charitable foundation, a private foundation does not generally solicit funds from the public. And a private foundation does not have the legal requirements and reporting responsibilities of a registered, non-profit or charitable foundation. Not all foundations engage in philanthropy: some private foundations are used for estate planning purposes.
One of the characteristics of the legal entities existing under the status of "Foundations" is a wide diversity of structures and purposes. Nevertheless, there are some common structural elements that are the first observed under legal scrutiny or classification.
Some of the above must be, in most jurisdictions, expressed in the document of establishment. Others may be provided by the supervising authority at each particular jurisdiction.
Foundations were first introduced in The Bahamas in December 2004 following the Foundations Act. 
A private foundation, in the United States, is a charitable organization described in the Internal Revenue Code by section 509. A private foundation is necessarily a 501(c)(3) exempt organization (or a former such entity). It is defined by a negative definition: by what it is not. A private foundation is not a public charity, as described in section 170(b)(1)(A) (i) through (vi). Neither is it a section 509(a)(2) organization, nor a supporting organization. Private foundations are subject to 2% excise taxes found in section 4940 through 4945 of the internal revenue code. Once a charity becomes a private foundation, it retains that status unless it follows the difficult termination rules of section 507.
The following foundations are set up under civil law legal systems:
The Austrian Private Foundation (Privatstiftung) was last reformed under the Private Foundation Act in September 1993.
In Canada the Canada Revenue Agency is a branch of the Canadian government which regulates all foundations. Under Canadian law, since 1967, a private foundation is controlled by a single donor or family through a board that is made up of a majority (more than 50%) of directors at non-arm’s length. It is a legally registered charity with the Canada Revenue Agency. A public foundation is governed by a board that is made up of a majority of directors at arm’s length. A private foundation is not allowed to engage in any business activity, but it can operate its own charitable program.
Canada Revenue Agency designates the application as a “charitable organization,” a “public foundation,” or a “private foundation,” depending on its structure, its source of funding and its operation. The Income Tax Act requirements are different, depending on the type of charity.(Canada Income Tax Act, R.S.C. 1985 (5th supp.) c. 1, para. 149.1(4)(a))
The Liechtenstein Family Foundation (Stiftung) was first introduced in 1926.
The Mauritius Foundation was introduced following 'The Foundations Act' of 2012.
A foundation in the Netherlands (Stichting) is a legal person created through a legal act. This act is usually either a notarised deed (or a will) that contains the articles of the foundation which must include the first appointed board.
Foundation legislation was last reformed in 1998, giving rise to the Netherlands Antilles Private Foundation (Stichting Particulier Fonds).
The Nevis Multiform Foundation was introduced in 2005.
The Panama Private Interest Foundation was introduced in 1995, modelled on the Liechtenstein Family Foundation.
The Saint Kitts Foundation was introduced following the Foundation Act of 2003.
The Seychelles Foundation was introduced following the Foundation Act of 2009.
A private foundation in Sweden (Stiftelse) is formed by a letter of donation from a founder donating funds or assets to be administered for a specific purpose. A private foundation may have diverse purposes, including collective, familiar, or the purpose of passive administration of funds. Normally, the supervision of a private foundation is done by the county government where the foundation has its domicile, however, large foundations must be registered by the County Administrative Board (CAB), which must also supervise the administration of the foundation. The main legal instruments governing private foundations in Sweden are those that regulate foundations in general: the Foundation Act (1994:1220) and the Regulation for Foundations (1995:1280).
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