Solicitors acting for Mary Danowski (nee Moore) and her three children said they were considering appealing against the ruling by Mr Justice Evans-Lombe in the High Court at the end of a six-week hearing. Mrs Danowski was on holiday with her family in South Africa.
The Henry Moore Foundation, a charitable trust, was set up by the sculptor in 1977 to avoid tax on works sold and to keep his works intact.
He died in 1986, aged 88. The foundation was given his personal collection, and for the final 10 years of his life paid Moore pounds 45,000-a-year salary. In return his works during that time became the property of the trust, which sold them. Up to 1977 he had been self-employed, and paid income tax on all his sales.
Mrs Danowski, who was suing as one of the trustees of her parents' wills, wanted a ruling that unsold sculptures and other works by her father in the last 10 years of his life remained his personal property and should therefore have passed to her.
The most important works in dispute were the 'artist's copies' of Moore's limited edition sculptures. By convention, any artist is allowed to make an extra two copies of a work, to keep or sell. Moore used to give these to his family, but after 1977 gave the artist's copies to the foundation.
The judge held that the 1977 agreement was unambiguous and plainly said the ownership of work executed under its terms was vested in the company. On the same basis, artist's copies made after 1977, created out of materials provided by the company and using its facilities, also belonged to the company.
The foundation owns 700 Henry Moore sculptures, including large monuments, working models and maquettes. If it had lost the case, half of these would have passed out of its control, including 30 of the largest 50 sculptures.
The foundation has suffered an increasingly acrimonious relationship with Mrs Danowski, who ceased being a trustee in 1980.
The difference of opinion came to a head last year over plans by the foundation to build new tourist facilities at Moore's former home in Perry Green, Hertfordshire, such as coach parks and a viewing tower, and demolish a barn which Moore used as a studio.
According to his daughter, the proposals, which were rejected by the Department of the Environment, contravened the spirit of her father's legacy.