Snomax should not be considered as a genetically modified organism (GMO), but Ice-minus should.
GMOs are defined as any organism whose genes have been altered in order to give it characteristics and functions that are not part of its nature. Since Pseudomonas syringae is a naturally ice-nucleating bacteria, Snomax is in accordance to the organism's nature. However, by deleting its ice-nucleating gene, and turning it into an anti-freeze for crops, the bacteria can be considered as altered.