[5] In October 2012, the Bloomberg Billionaires List ranked Mars as the 31st richest man in the world with an estimated net worth of $20.1 billion.

[3] As owner of the Diamond Cross Ranch, an 82,000-acre (33,000 ha) parcel along Montana's Tongue River and on the northern end of the Powder River Basin, Mars was active in opposing the development of his part of what's been called the "most productive coal and natural gas fields in the nation.

"[9] Companies that hold the oil and gas leases to his land, rights originally made possible by the Stock-Raising Homestead Act and the Mineral Leasing Act, are seeking to exercise those rights on his ranch.

[10] The ex-couple made significant contributions to the privately owned governing body for Fort Ticonderoga, though a falling-out between Executive Director Nicholas Westbrook and Mrs. Mars led to her resignation from the board and the end of the then-couple's financial support.

[18] Mars died at age 84 on July 26, 2016, in Seattle, Washington, of complications from a heart attack.