The wife of Pacific Investment Management Co. co-founder and billionaire Bill Gross is seeking a divorce after 31 years of marriage and their joint work on a charitable foundation that gave away almost $800 million.

Sue Gross said the couple have “irreconcilable differences” in a petition filed Nov. 22 in Los Angeles state court. The filing contained no further details, stating that Sue Gross is as yet unaware of the nature and extent of the couple’s assets and obligations.

The couple married in 1985 and Sue is Bill Gross’s second wife. Their William and Sue Gross Family Foundation had donated almost $800 million as of January, including a $40 million gift that month to create a school of nursing at the University of California, Irvine. The foundation also donated $38 million to Doctors Without Borders and $23.5 million to Duke University, according to a statement by University of California at Irvine.

Gross, 72, is worth an estimated $2.1 billion, according to data compiled by Bloomberg.

He co-founded Pacific Investment Management Co. in 1971 and led investing at the asset management firm until he resigned in 2014 amid a clash with other executives at the firm. Gross, who now runs the $1.7 billion Janus Global Unconstrained Bond Fund, sued Pimco last year for “hundreds of millions of dollars,” contending he was ousted by a “cabal” of colleagues who sought to avoid paying his $200 million bonus.

Seth Lubove, a spokesman for Gross, declined to comment on the divorce petition. Sue Gross’s lawyer, Laura Wasser, didn’t immediately respond to an e-mail seeking comment.

The case is Gross v. Gross, BD649294, California Superior Court, Los Angeles County.