"The [Anne Frank House] stated it's goals as 'the restoration of 263 Prinsengracht' and 'the propagation of the ideals left as a legacy to the world in the diary of Anne Frank.'"
The Hidden Life of Otto Frank p. 262

"To Otto [Frank]'s distress, [the Anne Frank House] was not running as smoothly as he had hoped, and he had many disagreements with the board, who he felt did not have enough interest in the educational aspect of the organization. With his faith in his vision of the [AFH] shaken, he decided that upon his death the copyright on Anne's diaries and other writings would be inherited by another group, the Anne Frank-Fonds in Basel."
Hidden Life of Otto Frank p 276-7

(Reading Muller's biography of Anne Frank and The Hidden Life of Otto Frank, it appears that Otto Frank left very little to the Anne Frank House, upon his death in 1980. Specifically: items he'd forgotten that were not needed elsewhere. HLOF p. 310)