The great-grandchildren of the founder of Barq’s root beer are suing the Coca-Cola Company, claiming Coca-Cola doesn’t legally own their share of Barq’s.

The suit, filed in U.S. District Court in Louisiana, outlines the long and complicated history of the Barq’s family in Louisiana and Mississippi dating back more than a century.

The suit seeks an unspecified amount.

Coca-Cola spokesman Kel Villarrubia told The Times-Picayune that the claims are bogus.

The estate of Arthur Louis Robinson filed the suit. Robinson’s children claim Coca-Cola didn’t have the legal right to purchase a certain one-third share of the Barq’s company when its acquisition was made in 1995, despite signed contracts to the contrary.

Coca-Cola purchased Barq’s for $91 million.

The suit ultimately seeks to overturn an agreement Robinson signed in 1971 giving over his portion of the company to his sisters.

The Barq’s story begins in about 1890, when Edward Charles Edmond Barq Sr. created Barq Brothers Bottling Co. in the French Quarter, according to the lawsuit.

Barq stopped operating the company in 1897 and moved to Biloxi, Miss., where he founded the Biloxi Artesian Bottling Works in 1899. By 1901, he was selling a sarsaparilla-based drink called Barq’s in Biloxi.

According to the suit, at some point in the early 1900s, Barq fathered a child, Jasper “Jesse” Louis Robinson, out of wedlock. Robinson lived with the Barq family.

The suit alleges that Robinson, at the urging of Barq, created and operated a Barq’s production facility in New Orleans. In 1934, Barq gave Robinson the right to use the Barq’s formula and name to sell root beer in all of Louisiana, excluding Washington Parish, while Barq maintained the exclusive rights to operate in Mississippi.

In 1936, Barq dissolved Biloxi Artesian Bottling Works and created Barq’s Inc. to operate the Mississippi Barq’s enterprise. Ten years later, after Barq died, Robinson formed Barq’s Beverages Inc. to oversee the Louisiana territories.

When Robinson died in 1949, he left half of the company to his wife, Marie Vicknair Robinson. The other half was to be divided three ways between his children, including Jesse Robinson, who was named president by his mother. The children were also to divide evenly their mother’s share upon her death. Robinson, however, was ousted from the company by his sisters in 1971 and sold his one-third share to them upon his departure. He also sold, according to documents, his planned inheritance.

The latter is the basis for the suit. Robinson’s estate argues that it is not possible to sell an inheritance under Louisiana law, said the estate’s attorney, Andrew Kramer.

That Robinson did so makes the entire contract null and void and means he still had an interest in the Louisiana Barq’s company, which went on to merge with the Mississippi company before being sold to Coca-Cola in 1995 for $91 million. Robinson died in 1996.

He is succeeded by three children.

They are asking for one-third interest in the “fruits and revenues generated and produced” by the acquisition of Barq’s “including, without limitation, the increase in value of those rights, the revenues generated from the use of the Barq’s trademark” in Louisiana. The estate is also asking for a share of stock in the Coca-Cola company that would be equal to the amount Robinson held in the Barq’s brand or some monetary compensation.