It's now up to a three-judge panel to decide if the Lin family had a valid contract with the city to build 51 homes on land the Lins own above Kottinger Ranch in a project called Oak Grove, or if, as the city claims, the Lins did not.

Jennifer and Fredric Lin want to build 51 homes on their 600 acres in the southeast hills of Pleasanton, but their plan was blocked by voters in 2010.

On Wednesday, three judges from the California Court of Appeal in San Francisco heard from the Lins' attorney, in what may be their final effort to overturn earlier court decisions, which back Pleasanton's claims.

At issue is whether a development agreement between the city and the family was valid. Andrew Sabey, attorney for the Lins, told the judges that the development agreement should stand, even though voters stopped the homes from being built through a referendum, Measure D.

Sabey said the family and the city worked for four years to hammer out an agreement, and claimed the opponents of the plan chose the wrong document to bring to a referendum. Sabey claimed the vote, which focused on Ordinance No. 1961, did not affect the development agreement, which specified various aspects of the project, authorized by Ordinance No. 1962.

"The development agreement is adopted after 30 days," Sabey said. "You have a vested right."

Both ordinances were approved by the City Council, but a grassroots group led by former City Councilwoman Kay Ayala and Karla Brown -- who has since been elected to City council -- successfully brought Ordinance No. 1961 to a referendum.

"In order for any city in California to enter into a development agreement, they have to approve it by ordinance," said Amrit Kulkarni, who represented Pleasanton in the case.

Kulkarni explained that the ordinance had specific language that said the ordinance would be void if voters opposed it.

"Without an approval, you can't have a contract," he said.

Sabey maintained that the city's development agreement should stand, regardless of the outcome of the referendum.

"You can't stand on the whims of the voters," he said.

A ruling on the case is expected within the next 30 days, according to Pleasanton City Attorney Jonathan Lowell, who attended the hearing on Wednesday, accompanied by Ayala, Brown, former City Councilwoman Cindy McGovern, Assistant City Attorney Larissa Seto and Allen Roberts, a homeowner who also opposed the project, known as Oak Grove.

The family lost its last attempt at getting the project approved, two years ago. In that case, Alameda County Superior Court Judge Yvonne Gonzalez Rogers ruled in March 2012 that both the ordinances involved were voided when one of them was overturned in the referendum due to "poison pill" language, which essentially killed Ordinance 1962 when voters overturned Ordinance 1961.

But the battle between the mother and son Lin family and Pleasanton is not over.

"If this decision goes against them, they have the opportunity to petition for review before the California Supreme Court," Lowell said. "The chances of the Supreme Court hearing the petition are pretty slim."

However, the Lins have another lawsuit that has been put on hold until a ruling from the Wednesday hearing.

"In that one, they're seeking damages, saying the city's actions have harmed them monetarily," Lowell said.

That suit is several million dollars.

The Lins also have submitted plans for a much smaller development -- 10 large lots for single-family custom homes -- on the site.

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