Two philanthropists from Maine have pledged, along with other billionaires including Warren Buffett and Bill Gates, to donate most of their wealth to charity.

Bernard Osher and Marion Sandler, a brother and sister who are Biddeford natives, appear to be the first Mainers who have made the pledge, according to the website of the Giving Pledge.

Forty individuals and families have committed, through the Giving Pledge, to give most of their wealth to philanthropic causes and charitable organizations, either during their lives or after they die. The list includes film director George Lucas, fashion designer Diane von Furstenburg, New York City Mayor Michael Bloomberg and Ted Turner.

In a letter explaining the reason for their donation, Sandler and her husband, Herbert, cited the harm that wealth can do when it is passed down through generations.

“There is no way to spend a fortune. How many residences, automobiles, airplanes and other luxury items can one acquire and use?” the couple wrote in the letter announcing their pledge.

Osher and the Bernard Osher Foundation have no comment regarding the pledge, said Jeanie Harokane, a corporate secretary for the foundation who responded to a request for an interview.

The Giving Pledge was founded by Buffett, chief executive officer of Berkshire Hathaway. The pledge is a moral commitment, not a legal obligation, and doesn’t involve pooling money or advocating for any cause or charitable organization.

“At its core, the Giving Pledge is about asking wealthy families to have important conversations about their wealth and how it will be used,” Buffett said in a news release. “We’re delighted that so many people are doing just that — and that so many have decided to not only take this pledge but also to commit to sums far greater than the 50 percent minimum level.”

Osher, a Bowdoin College alumnus, and his wife, Barbro, live in California but maintain a home in Scarborough.

Osher had a hardware store in Biddeford before he worked for Oppenheimer & Co. in New York. He was the director of World Savings, the second-largest savings institution in the country, and owner of Butterfield & Butterfield, a large auction house that he sold to eBay.

A 2005 article in Forbes magazine estimated his wealth at $1.1 billion.

The Bernard Osher Foundation, established in 1977, funds college scholarships and centers for integrative medicine and lifelong learning. The centers’ national headquarters were established at the National Resource Center at the University of Southern Maine in 2004.

“They are wonderful friends of the university and have been great supporters and contributors and have been very innovative in their giving,” said Meg Weston, president of the USM Foundation and the university’s vice president for advancement.

The Oshers have donated upwards of $10 million to USM, including the Osher Re-entry Scholarship, for a student who wants to return to college to complete a degree.

Sandler and her husband have pledged to donate all of their wealth to a variety of causes, including the American Asthma Foundation; ProPublica, an investigative journalism website; and a progressive think tank, the Center for American Progress.

The same 2005 Forbes article pegged Sandler’s net worth at $1 billion.

In 2006, the couple donated $1.3 billion to their philanthropic foundation, the Sandler Family Supporting Foundation.

The couple founded Golden West Financial Corp., which later became World Savings Bank. It was sold to Wachovia in 2006 for $24 billion.

Staff Writer Stephanie Hardiman can be contacted at 791-6301 or at:

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