The court heard that developer Snowy Owl 90 Pty Ltd offered in writing to purchase the property for R10m.
Apart from this, Snowy Owl also agreed to contribute R2m for the exclusive purpose of renovating, upgrading and maintaining the museum.
The administrators of the estate of the late Samuel Marks launched the application in court pertaining to a particular clause in Marks' will, which he made in 1892. Marks died on February 18 1920.
The clause, which was brought under Acting Judge John Mullins' attention, read that the farm Zwartkoppies may not be sold or disposed of while three generations of his descendants were still alive.
"Only after the demise of the survivor of the third generation of his descendants shall the said property be sold and the proceeds paid out to his heirs then alive...," the clause read.
Mullins said there were clearly many years to go before the end of the third generation. The last of his children, Fanny Beatrice Maisels, died on May 30 1992.
According to court papers there are four surviving grandchildren - the youngest being 77 and 12 great grandchildren. The youngest is 45 and the oldest 56.
The fourth generation consists of 26 great-great-grandchildren the youngest being Sean Patrick O'Dwyer, who is around one-year-old.
Only one descendant lives in South Africa. The rest are scattered all over the world, including in Scotland, France, Italy, Canada and England.
The court heard that most of the property in question has been expropriated, leaving only three portions which lie adjacent to each other and form one farm.
A portion of the farm (about 73ha) on which the Marks' home stands, was expropriated by the State in 1995 for a total price of R1,045,000. The house now serves as a national monument - the Sammy Marks Museum which is open to the public.
The family said the remaining three portions of the farm (the subject of the application) brought in very little income and it was used for grazing.
"Consequently, the farm is presently let to the National Flagship Institution (the legal successor-in-title to the National Cultural History Museum) for an annual rent of R100."
He said the property was at present a liability, as the estate was obliged to contribute R1800 a month towards the museum's upkeep.
The court heard there had been several offers for the farm, including an offer in 2003 to purchase it for R6 million. This offer was rejected.
The administrators of the estate, however, accepted the R10 million offered by Snowy Owl.
"They do so with the unanimous support of every singe one of the second and third generations of beneficiaries," the judge said.
The family indicated they were not interested in farming on the land.