Rick and Marty bought half the Oak Island from Oak Island Tours Inc, the company that owns the island. Dan Blankenship privately owned the land.

Now that he is no more, the owner is his son Dave, who lives on the island. In 2006, the Laginas brothers purchased 50% of the stake from the company and became the majority lots owner of the land.

They bought the share in the land when they originally began treasure-hunting. Before this, both brothers were engaged in different professions.

The total area of Oak Island is divided into 32 lots by Oak Island treasure, per the Looper. The Lagunas are the owner of most of the land and even run a TV show based on their treasure hunt. 

The brothers have been digging around the land of Oak Island in search of the treasure for more than eight years. They have been presenting the whole process of their treasure hunt on the television series The Curse of Oak Island through the History Channel. 

The brothers have bought the land on the island, getting fascinated by the rumors of treasure. They have planned to find the secret treasure, but to date, they have not seen anything like treasure. 

However, while searching in Lot 21, the men found an antique brooch of copper and gold with a red gem estimated at least 500 years old by The Sun. Several other coins that may be 200 years old are also found. 

Many other historically significant materials have been found in the different areas of the Island. Some pieces of gold, old hand-painted Pottery, metal ring, brooches, decorated piece of lead, military cap badges, and many others came out to form the land as per Looper.

Over the past century, countless companies, groups, and even individuals have searched high and low for this hidden treasure supposedly buried somewhere on the island. Dan, the owner himself, has spent most of his life looking for the treasure and passed away in 2019 at 95.

The majority of the total area of the land is owned by The Michigan Group run by the Lagina brothers. The rest is owned by others.

Among all the lots, six are owned by Allan Kostrzewa, and the other three are owned by the son of the late Fred Nolan, Tom Nolan. Allan is one of the producers of the treasure hunt show, and Fred has officially been permitted to search and dig.

The rest of the owners are not linked with the show. Robert Young owns lot five, and J.D. Johnson holds Lot 13. These are the only areas left to be explored by the men of The Curse of Oak Island out of 32 lots of land. 

The land value on Oak Island is based on the total square feet occupied by the lot. It varies according to the selected area among the 32 divided lots. For a lot occupying 7841 sq ft on Oak Island, it will cost $435,000, as per Zillow.

According to history, the amount the brothers have spent on the island purchase is never disclosed to the world. However, they have spent a lot even after paying Mr. Dan, the owner, their drilling and digging for their hunt each year.

They are using better and bigger technologies in the land for their show.