John Menard Jr., founder of the Menards store chain, doesn't owe his ex-fiancée a dime of his billions, the state's Supreme Court ruled Friday.

The third time was not the charm for Debra K. Sands, who suffered the same legal losses in Eau Claire County Circuit Court and last year at the Court of Appeals.

Sands claims that Menard, his various companies and trusts owe her a stake for the work she did while she was Menard's live-in partner from 1998 to 2006, as well as millions in legal fees she said she earned.

But in a 5-2 decision, the Supreme Court distinguished the Sands-Menard enterprise from those of a case that set out when one person is unjustly enriched by the efforts of the partner.

"Sands, however, did not support Menard as he built his empire; he already had it when they met," Chief Justice Patience Roggensack wrote for the majority.

Also, the majority found, any benefits Sands did confer to Menard or his businesses was more than offset by benefits she received as his girlfriend, including a new Ford Mustang, law school loan repayment and numerous trips to the Caribbean, London, Italy and around the U.S.

Justices Shirley Abrahamson and Ann Walsh Bradley dissented on the issue. They found Sands had presented sufficient facts about her unjust enrichment claim to survive Menard's motion for summary judgment and go to trial.

"The fact that Menard was already successful does not preclude Sands' unjust enrichment claim if Menard's assets became more valuable as a result of the parties' joint efforts," Abrahamson wrote.

Menard, 77, has an estimated net worth of $9.9 billion, according to Forbes magazine, making him the 47th richest person in the nation and number one in Wisconsin.

RELATED:Forbes 400: Menard remains Wisconsin's richest person, while Faulkner and Hendricks climb

Sands, a Minnesota lawyer, began dating Menard in 1997, four years after she graduated from William Mitchell College of Law. She moved in with him in 1998, a fact he disputes, though he admits they were engaged.

According to Sands, during their relationship, she did everything from manage his health care and residential remodelings to advising him on airplane purchases and Menard Inc. marketing plans, as well as helping to manage Menard's horse racing enterprise and a $400 million private equity fund.

Menard Inc. did pay Sands $152,105 for legal services she provided between April 2003 and June 2004. And when the couple broke up in 2006, Sands was offered more than $1 million to settle her other legal fee claims, provided she sign a release waiving any "quasi-marital claims" as well, according to court documents.

Sands declined and sued in 2008 for unjust enrichment, breach of contract and other claims. She sought a share of the increase in Menard's net worth during the period she was his girlfriend and "acquired through her efforts."

The legal work Menard says Sands did perform — during an environmental action in 1997 — she says was really just a fake invoice meant to disguise his payment of her unpaid law school loans.

Sands broke up with Menard in 2006, around the time he fired her sister, Dawn Sands, who had served as general counsel to Menard Inc. Dawn Sands also sued and won more than $1 million until the judgment was reversed.