Commercial or Proprietary?

Khanna and Ranganathan wrote up a review paper on molecular similarity (doi:10.1002/ddr.20404). I have not fully read it yet, but my eye fell on Table 1, which lists a number of programs that can be used to calculate QSAR descriptors, both open source and proprietary.

However, the table features a column Availability which has two options: Public, Commercial. They qualify Bioclipse, CDK, and RDKit as public, and Dragon, MOE, CODESSA and others are commercial. Effectively, it seems to suggest that they classify them as open source versus commercial, though I am not entirely sure what they mean with public.

It is very important to realize the Open Source software can be commercial. For example, you can get commercial support for Bioclipse and CDK withGenettaSoft. It is also really important to realize that free software (public?) does not mean it is Open Source (or visa versa).

E-Dragon is an example here: you can freely use, but the source code is proprietary. Some years after open source cheminformatics took off, commercial providers started to provide free-for-academic-use packages, which fits into this category too.