[9] With the money he made from his first company, Resnick bought The Franklin Mint, a subsidiary of Roll International Corporation, in 1986.

[11] Franklin Mint is known for making model cars, souvenir plates, figurines, and Civil War-inspired chess sets.

[5] Since 1979 Resnick has served as President and chairman of The Wonderful Company, formerly known as Roll Global, which owns many businesses in Central California and beyond.

These including the Louvre art museum in Paris, the Vatican,[15] board games like Monopoly and Scrabble, classic cars, and famous people like John Wayne, Elvis Presley, and Marilyn Monroe.

[34] During the 2011–2017 California drought—also called the Great Drought—Resnick's Paramount Farms, which is part of the Wonderful Company, drilled twenty-one new wells in 2015 alone.

The acquisition, continuing private ownership, and water sales profit from this taxpayer-developed resource infrastructure, while California suffers under drought, is controversial.

[10][36] Growing water-intensive nut tree crops in the Central Valley—a single almond can require up to 1.1 US gallons (4.2 L) of water[37]—has drawn criticism during California's ongoing drought.

According to Forbes magazine, the Wonderful Company uses "at least 120 billion gallons [450 million m3] a year, two-thirds on nuts, enough to supply San Francisco's 852,000 residents for a decade".

[38] In an effort to make their impact on the region more positive, the Resnicks have invested in the growth of the local economy and nutrition centers.

Forbes reported, "The Federal Trade Commission filed a complaint in 2010 that the Resnicks' POM Wonderful had used deceptive advertising when marketing the antioxidant-rich drink as being able to treat, prevent or reduce the risk of heart disease, prostate cancer and erectile dysfunction.

[47] Resnick is a trustee emeritus of the J. Paul Getty Trust[48] and is on the board of visitors of the UCLA Anderson School of Management.

[50][51] He also serves on the board of advisers at UC Davis, the Lowell Milken Institute for Business Law & Policy at UCLA, and is a Caltech senior trustee.

[57] In 2018, the Hammer Museum in Los Angeles announced the couple's $30 million gift to help pay for a renovation and expansion project.

[58] In September 2019, Resnick and his wife pledged their largest donation to date, a $750 million endowment to Caltech for climate research.