Oyster Pond on Martha’s Vineyard may be one of the most serene spots in the state, but it has given rise to remarkably contentious, long-running, and confounding court battles.

The combatants include a handful of wealthy families, fighting for control of nearly two miles of remote beach bordering the Atlantic Ocean. The strange question at the heart of their dispute: When a beach — over many generations — changes location, who has the rights to it? The old owners? The owners of the spot where it has migrated? Or, in this particular case, perhaps the public?

The question is more complicated than it might sound. And it could have a far-reaching impact on the state’s coastline as global warming raises ocean levels and shifts beaches.

The matter has occupied the state Land Court, the Appeals Court, the Supreme Judicial Court, and the Legislature. Just recently, the SJC threw up its hands over the situation, rejecting a plea from lawmakers to help sort out the ownership dispute because their questions were too murky.

“The meaning of some of the significant terms and concepts,’’ the justices said, “are unclear to us. A complete answer may depend on facts and circumstances we do not have before us.’’

A chief actor in this drama is Richard Friedman, the Boston real estate mogul who developed the Charles Hotel in Cambridge and the Liberty Hotel in Boston, among other notable properties. His vacation home served as the Summer White House during Bill Clinton’s presidency.

When he bought his property, a secluded 20 acres at the upper reaches of Oyster Pond in Edgartown back in 1983, he was convinced that his deed gave him ownership rights to a barrier beach, separating the 208-acre pond from the ocean.

His neighbors disagreed, prompting several lawsuits. But as the litigation persisted, he and his legal team came up with a different argument. That section of the beach, they now contend, should belong to the public.

Friedman said the rarefied squabble opened his eyes to the public’s lack of access to many beaches on Martha’s Vineyard. “A dispute about access and use of a beach over a decade ago has become less about my rights and all about public rights,’’ he said. “All the legal mumbo jumbo got me to focus on an issue that I felt was unjust, and I pushed for a solution that is fair and right.’’

But his persistence has frustrated those on the other side of this fight. Attorney Brian Hurley compared it to a Dickens novel about an endless 19th-century court fight. “The legal battle about ownership and rights to use this isolated stretch of private beach has been extraordinarily lengthy and expensive. It is reminiscent of Bleak House,’’ he said.

At the center of the fight are two large areas that had been farmed for centuries. By the mid-1900s they were owned by two families, the Nortons and the Flynns, whose descendants carved up the land into several large estates. The Norton land is owned by three realty trusts; Friedman is the principal of one. The Flynn land is under the ownership of six trusts.

Citing old deeds and customs, Friedman and a handful of neighbors on the Norton land believed that they could claim ownership of a bit of the beach that the Nortons had used for years. Complicating their claim: The beach had shifted over the years — or “accreted’’ — northerly onto the island’s south coast.

The section of the beach that Friedman’s deed gave him rights to was a small sliver that, by the mid-20th century, had moved into Oyster Pond itself.

The Flynn landowners objected to their claim, saying Friedman’s property was legally under water, 200 feet offshore. And the rest of the beach, they said, belonged to them.

Friedman and the other homeowners on the Norton land began legal proceedings to establish their ownership. They failed in the state Land Court in 2011 and on an appeal two years later to the Supreme Judicial Court, essentially losing any rights to the Flynn beach.

The SJC, however, in the same case, sent back to the Land Court another issue that still lingers in the lower court: Friedman and other Norton landowners’ claims to easement rights to use the beach. They argue that because the Flynn landowners had allowed them to use it for years, they should still have that right.

Meanwhile, Friedman and his advisers came up with a new legal theory about the beach. Oyster Pond, they note, is legally a “great pond’’ — at least 10 acres — which Massachusetts law considers public property. His team, citing the Colonial Ordinance of 1641-47 and centuries of court rulings, argues that because the beach had moved onto public property, it is now public land and therefore open to public use.

Friedman turned to Beacon Hill. With the help of William F. Coyne Jr., one of the State House’s most experienced lobbyists, he has for several years pushed legislation declaring that barrier beaches that move into already publicly owned great ponds become public property.

The lawyers for the trusts on the old Flynn land are fighting back, claiming that Friedman’s bill comes with a heavy financial burden for Massachusetts taxpayers because the state would be taking privately held land and therefore would be required to reimburse the owners, a finding that could be applied across the state.

Friedman’s team estimates that there are 28 similar beaches the Massachusetts coast that are now considered private property and that under his bill would be declared public.

His opponents also say the people who could benefit most from the legislation are Friedman and a few neighbors because the property is remote and access to any declared public beach would be difficult.

“While he would certainly benefit, the bill would wreak havoc on the property rights of thousands of people in Massachusetts, exposing taxpayers to suits for land takings, just so that he can get access to someone else’s property,’’ said Jim McManus, a spokesman for the coalition battling Friedman and his neighbors.

Friedman scoffs at that notion — and notes that after buying an additional piece of land, he personally has deeded-rights to the beach.

After year of legal wrangling, most would be ready to give up. But Friedman, caught in a Bermuda Triangle of litigation, seems determined to press on, at least on one issue that he now claims is close this heart. He said he will continue to push to open up that small section of the beach at Oyster Pond to the public.

“While I personally enjoy beach rights,’’ he said, “I plan to continue to advocate for right of members of the public to have access to and use of what is theirs.’’

Frank Phillips can be reached at phillips@globe.com.