Ambiguous definition of Derivative

[maxashen]

Derivative: Software which includes any portion of the Mod other than the API, with modifications, additions, or subtractions.

Normally I see the term "derivative work" which means that the work is based on a previous, "derived" work and includes copyrightable portions of the derived work. From this I can assume that this license's definition would be better written as follows:

Derivative: Software which includes any portion of the Mod other than the API. A modified version of the Mod is considered a Derivative.

Compare this with another interpretation:

Derivative: Software which includes any portion of the Mod other than the API, including modifications, additions, or subtractions to the Mod.

Yet another one, which provides a definition for "modifications"

Derivative: Software which includes any portion of the Mod other than the API, including modifications to the Mod (additions or subtractions)

And here's a less likely interpretation:

Derivative: Software which includes any portion of the Mod other than the API, including modifications, additions, or subtractions to the API.