There are two important organizations dealing with the legacy of Anne Frank.

One is the Anne Frank Fonds in Basel, Switzerland. This is set up by Otto Frank, Anne's father. The Anne Frank Fonds is the owner of the copyrights on Anne Frank's diary.

The other one is the Anne Frank Stichting (Foundation). It owns and runs the hide-out at Prinsengracht 283, which is now the Anne Frank House, one of the most famous tourist attractions in Amsterdam.
The original diary is owned by the State of the Netherlands (which was Otto Frank's last will). The diary has been given on a permanent loan to the Anne Frank House, where it is displayed.

The two organizations currently don't get along very well. They argue about the legacy of Anne Frank, Anne Frank as an officially deposited brand name, and about archives.

The Anne Frank Fonds in Switzerland wants to set up a Frank Family center in Frankfurt (where the Frank family originally came from). To that purpose it has demanded documents and files back from the Anne Frank House in Amsterdam. This has lead to a legal fight.

Read more about the brand name application.