FoundationMark is a division of Foundation Financial Research LLC, a grantmaker-focused financial analytics firm founded and operated by John Seitz, a former investment manager and consultant.
FoundationMark’s parent company is Foundation Financial Research, a limited liability company founded on February 5, 2015 by John Seitz, a former investment manager, and registered in Lewes, Delaware.  The firm focuses on providing financial analytics services focused on the investment performance of private foundations based off of publicly available data to foundations and the general public. 
Aside from FoundationMark, the company has two other divisions. The first is FoundationIQ, which offers information about roughly 40,000 private foundations with assets of at least $1million to clients via proprietary search tools that track measures such as investment performance, asset allocation, holding data, feed paid. The second is FoundationAdvocate, which offers newsletters, lists, and links oriented around news about foundations, particularly about issues, details, and policies affecting their general investment performance.   
Indices and Metrics
FoundationMark publishes several financial indices derived from publicly available investment data gleaned from organizational filings with the IRS. The most notable index is the GIV (Grantmaker Investment Value) Index, which tracks the annual investment performance of roughly 40,000 private foundations with assets over $1 million, based on disclosed investment expenses (management or trading fees), the composition of assets in a foundation’s portfolio, and the timing of cash flows such as investment dividends and donations. 
Aside from the GIV Index, another notable FoundationMark index is FoundationMark15, a list of the 15 largest and well-known private foundations in the United States. For instance, the 2021 FoundationMark15 includes the Bill and Melinda Gates Foundation, Ford Foundation, and Bloomberg Family Foundation. Aside from foundations’ positional rankings on the list, which is updated annually, FoundationMark also assigns each foundation a rating of between one and five for their investment performance over the preceding one, three, and five years.  FoundationMark also maintains and publishes additional, separate indices for foundations based on the month they choose to start their fiscal year. 
Additionally, the company publishes data and offers an interactive visualization illustrating foundations’ investment performance by asset class, including international equities, the S&P 500, high yield bonds, and emerging equities. 
FoundationMark offers free performance reports upon request to officers and trustees of private foundations, which feature analytics on a given foundation’s financial performance as compared to the roughly 40,000 foundations that the company monitors, as well as peer foundations (based on asset size and investment strategy). Key elements of this report include a 5-year summary of a foundation’s financial development, including grants and administrative expenses; an assessment of performance as compared to asset class; the grantmaker’s “FoundationMark star rating”; a review of the foundation’s publicly available disclosed investment expenses; and a short list of peer institutions in terms of size and investment strategy.  
John Seitz is CEO of FoundationMark as well as its parent company Foundation Financial Research LLC, which he founded on February 5, 2015. Previously, Seitz worked for various nonprofit organizations and also in various roles in portfolio management and equity research.