A judge ruled this week that an oceanfront property owner may continue to block public access to a Northern California beach, basing his decision on an unusual set of circumstances dating back to the mid-19th century.



San Mateo County Superior Court Judge Gerald Buchwald ruled that billionaire venture capitalist Vinod Khosla can legally block the only road to Martins Beach, which is a popular surfing spot south of Half Moon Bay. According to Thursday's ruling, beachgoers are still allowed to use the 200-acre beach -- if they can get there from the ocean.

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The San Francisco Chronicle reports that a lawyer who filed a lawsuit on behalf of the group Friends of Martins Beach plans to appeal the ruling, arguing that it violates beach access rights under the California Constitution.



Buchwald based his decision on the 1848 Treaty of Guadalupe Hidalgo, which settled the Mexican-American War, and required that the United States recognize Mexican land grants as long as the owner filed a claim. The original owner of the coastal property filed such a claim. The U.S. government challenged his land patent, but the U.S. Supreme Court confirmed his ownership in 1859 -- 14 years before the California Constitution was first drafted.



The decision is the latest blow in a years-long battle between beach lovers and Khosla, the Sun Microsystems Inc. co-founder who bought the property for $37.5 million in 2008. The Chronicle reports that after the sale, a gate was put on the road with a sign that said, ``Beach closed, keep out.''



Jeffrey Essner, attorney for Martins Beach LLC, said he was gratified by the decision.



``We are very aware of the community concern about the situation, and it is unfortunate that we were forced into the legal process rather than a conversation with the community,'' Essner said. ``The property owner strives to be a constructive member of the community, but it is difficult to have this conversation without the legal clarification on property rights and an acknowledgment of those rights.''