Some properties are considered mandatory while creating objects that it should not.

[joanma747]

While creating a Thing I was forced to specify the Party. This should be optional

While creating an observationGroup I has forced to specify a party. This should be optional

I'm not completely sure but I believe while creating an observationGroup I was also forced to provide a license.

I talking about a version installed in AD4GD servers so I'm not sure if it is the last version
https://frost.iotlab.com/sensorthings2/v1.1/ObservationGroups

[securedimensions]

The behavior you are describing is controlled by the STAplus plugin configuration.

The behavior is activated via plugins.staplus.enable.enforceOwnership=true. Effectively, it changes the cardinality to party to mandatory on all associations. No "dangling" entities that may later be associated with a Party are allowed in this mode.