These are the 20 largest endowments and foundations in the US

They have billions of dollars under management and investments in areas as varied as coal, US Treasury bonds, and sub-Saharan Africa real estate.

No, these aren’t private equity or Wall Street’s biggest hedge funds.

These are nonprofit organisations serving higher education, healthcare, and the arts.

Based on second-quarter data from 2014, the finance research and data site Graypools compiled a list dominated by higher-education institutions and interspersed with healthcare funds, art-preservation societies, and financing cooperatives.

Here are the top 20 foundations and endowments in the US by gross assets, based on their regulatory filings with the IRS.

Note: Gross assets data comes from Graypools, which may “significantly inflate an organisation’s “size” by failing to adjust for fully-secured liabilities, such as mortgages on development real estate.”

3. Yale University Investment fund

Yale University/Facebook

About: Yale University's investment fund reported a 20-year return of 13.9% per annum, giving $US20.6 billion in relative value added support to the Ivy League.

The University estimates that in the fiscal year that ended in June 2014, the endowment's invested donations under management totaled $US23.9 billion.

The revenues go toward professorships, scholarships and prizes, maintenance, books, and more.

Gross Assets: $US28.32 billion

4. Trustees of Princeton University

Wikimedia Commons

About: Princeton University's endowment fund has consistently ranked second largest among university endowments by assets under management.

In the fiscal year that ended June 30, 2014, it posted a 10-year average return of 10.5%.

The permanent endowment goes toward professorships, financial aid, and student activities, and it is managed by the Trustees of Princeton University -- the Ivy's governing board.

Gross Assets: $US20.81 billion

6. Howard Hughes Medical Institute

Wikipedia

About: Based out of New York, the Howard Hughes Medical Institute is the nation's largest private supporter of academic biomedical research. The organisation came about after Howard Hughes, the business tycoon and aviator, surrounded himself with a group of scientists and physicians.

The group would later create a medical institution based on Hughes' principles.

The institute also supplies funds for science education and gave roughly $US8 million to international research in the 2014 fiscal year.

Gross Assets: $US18.12 billion

7. Trustees of Columbia University

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About: Columbia University's endowment fund helps support professorships, financial aid, research, projects, centres, and more.

Twenty-six per cent of assets in 2013 were allocated to global equities, 20% to private equity, 32% to absolute return strategy funds, and 18% to real assets, according to the university's Office of Alumni and Development.

According to The New York Times, in October the university posted an annual return of 17.5%, coming behind the 2014 annual return rate of Yale (20.2%) and the much smaller endowment fund of Dartmouth College (19.2%).

Gross Assets: $US13.63 billion

8. Partners Healthcare Systems Inc.

Partners Healthcare

About: A Boston-based hospital and patient-care network that includes medical teaching institutions, Partners Healthcare has a hosts specialty hospitals, community health centres, and academic medical centres. The organisation also has a subsidiary biomedical research center.

Total operating revenue was $US2.8 billion in the three months that ended in December. The network is investing most of its money market pool in US Treasurys and overnight and short-dated commercial paper and money funds.

Gross Assets: $US12.6 billion

9. Harvard Management Private Equity Corporation

Facebook/HarvardMed

About: Supporting Harvard University, the corporation helps fund Harvard's endowment, and it is under the care of Harvard Management Company.

The corporation 'invests funds for the benefit of the President and Fellows of Harvard College, a related ... organisation' according to its 990 filing.

Gross Assets: $US11.14 billion

10. Ford Foundation

About: A New York-based organisation that focuses on social change, the organisation was created by Edsel and Henry Ford, the creator of Ford Motor Company.

The organisation has branched out into human-welfare projects around the world.

Its portfolio is made up of private equity, venture capital, growth equity, distressed investments, and hedge funds. The hedge fund portfolio alone makes up 25% of the foundation's endowment.

As of 2013, the foundation invested 51% of its funds in alternative investments and 20% in private equity and venture capital.

Gross Assets: $US10.98 billion

11. Emory University

Emory University/Facebook

About: In the fiscal year that ended in August 2014, Emory University's endowment generated returns of 18.2% -- adding close to $US1 billion in value to its portfolio.

According to university's investing team, the portfolio has more than $US7 billion in diversified investments that is overseen by both Emory University and Emory Healthcare.

It contributes funding to the university's scholarships and medical research.

Gross Assets: $US10.38 billion

12. Cleveland Clinic Foundation

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About: Based out of Ohio, the Cleveland Clinic Foundation helps fund the nonprofit academic medical center Cleveland Clinic.

In 2014, the foundation's endowment consisted of 261 donor-restricted funds, meaning funds have specific purposes, for example, to finance education, research, or healthcare.

The foundation expects an average return rate of 7.5% annually.

Contributions and grants increased nearly 13% from 2012 to 2013, according to the foundation's 990 filing -- at $US897.9 million. Program service revenue accounted for most of the foundation's gross assets, with $US3.2 billion.

Gross Assets: $US10.22 billion

12. Duke University

Duke Engineering/Facebook

About: The 'Ivy of the South,' Duke University's endowment is made up of more than 4,400 individual funds, totaling about $US7 billion, according to its website.

Like most university endowments, Duke delivers funding to scholarships, fellowships, professorships, programs, research, and more. Thirty-two per cent of funds are unrestricted and can be used however the university deems fit.

The endowment grew from $US3.2 billion in size in 2000 to $US7 billion in 2014. For 2014, the university also posted a 10-year annualized return rate of 10.8%.

Gross Assets: $US10.2 billion

14. Northwestern University

Northwestern University/Facebook

About: The university endowment fund has allocated assets largely to venture capital and global buyout funds (20%), and long-short equities (18%).

The 10-year annualized total return as of August 2014 clocked in at 9.6%. The fund grew from $US956 million in 1992 to about $US9.7 billion by August 2014.

Gross Assets: $US9.84 billion

15. University of Chicago

Via Wikimedia Commons

About: The University of Chicago's endowment had a market value of $US7.55 billion at the end of the 2014 fiscal year, according to its website.

In the same year, returns from the endowment's main portfolio -- which accounts for 96% of the endowment -- generated $US893 million, with annualized returns from the past 20 years clocking in at 11.2%.

The endowment is invested in an array of assets including global stocks and bonds, natural resources, private equity, absolute return strategies, and tail hedging strategies.

Gross Assets: $US9.62 billion

16. University of Notre Dame du Lac

Jonathan Daniel/Getty

About: The Catholic school has been increasingly focused on diversifying its portfolio because of geopolitical instability and US labour-market trends during the fiscal year that ended in June 2014.

The market value of the pool in 2014 increased to $US9.81 billion from $US8.32 billion -- meaning a 19.7% net of investment management fees.

The majority of assets went into public and private equities, with the returns helping fund $US300 million, or roughly 25%, of Notre Dame's activities that year, according to the university's Office of the Controller.

Gross Assets: $US9.33 billion

17. J. Paul Getty Trust

About: A cultural and philanthropic organisation that aims to cultivate interest in the arts and civil society, the Getty is also considered one of the world's wealthiest art societies.

The organisation collects, conserves, and curates artwork and gardens while educating people about the works.

Gross Assets: $US8.77 billion

18. Mayo Clinic

flick/cogdog

About: Consistently ranked among the best hospitals and teaching medical centres in the US, Mayo Clinic is a nonprofit medical-research group based out of Minnesota.

The clinic has several satellites around the country, and it is known for specializing in hard-to-treat cases.

Its endowment, made up of roughly 1,000 individual funds, helps provide operating expenses for research, educational programs, and more. In 2010, Mayo Clinic estimated that its endowment amounted to $US1.8 billion.

Five-year annualized returns in 2010 clocked in at 6.9%.

Gross Assets: $US8.53 billion

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