PLEASANTON -- For the third time in five years, a court has ruled in favor of Pleasanton and residents seeking to limit a pair of landowners' request to develop the city's southeast hillside.

The California state Court of Appeals ruled 3-0 on March 18 to affirm a previous court decision in which a judge found that a citizens' referendum was valid, negating a City Council approval for a 51-unit housing development known as Oak Grove and its accompanying development agreement.

Landowners Fredric and Jennifer Lin have argued that a 2007 City Council approval to build a 51-unit housing development with homes ranging in size from 7,000 to 12,000 square feet on 67 of the 562 acres they own near the end of Hearst Drive was separate from the development agreement and therefore separate from the citizen referendum that overturned the council approval.

In their 11-page ruling, Justices William R. McGuiness, Martin J. Jenkins and Peter J. Siggins wrote that, though development plans and development agreement were two documents receiving the City Council's approval, it was "not absolute but was made expressly subject to a condition subsequent, namely, a referendum setting aside (the development plan)."

Furthermore, the justices also affirmed that the Lins entered into the development agreement knowing the terms of the development plans that included "This ordinance shall be effective 30 days after its passage and adoption, provided, however, that if Ordinance No. 1961 is set aside by referendum, this ordinance shall be of no force or effect."

"We are thrilled that the litigation didn't outnumber the votes of the people of Pleasanton," said Kay Ayala, a former Pleasanton council member who led the referendum. "The litigation had no basis as far as I am concerned and thankfully the citizens went after the council approval with a referendum."

In addition to affirming the earlier decision, the court also awarded the city legal costs for defending against the suit. The Lins have 90 days from the decision to appeal the case to the California Supreme Court, but Pleasanton city attorney Jonathan Lowell said in an email that the likelihood of the Supreme Court hearing the case is slim.

In addition to the suit, the Lins also filed a damages suit against the city in 2011 for failure to honor the development agreement. The March 18 decision affirmed that the development agreement was not valid due to the referendum. Lowell said he would speak with the Lins' attorney about dismissing the damages suit.

The saga over the Oak Grove development began in 2007 after the council approved the project 4-1 that also included the Lins donating 495 acres to the city as open space and giving Pleasanton $1 million in traffic mitigation fees for a wild land fire truck.

Residents, led by Ayala, responded with the referendum that was approved by 54 percent of voters. The Lins challenged the referendum that spent three years in litigation before the court sided with the city in February 2011. During the court battle, residents also passed ordinances that protect and limit development in the city's hills.

The Lins also submitted a 10-unit plan for the land around the time they filed the damages suit but have since withdrawn that proposal, Lowell said.

"We are thrilled that this is over," Ayala said. "We are thrilled the city stuck in there and followed through."