While Adobe Photoshop, Illustrator, and Premiere were packaged under the moniker, Lightroom never officially used the "CS" prefix. At the time of the CS6 launch, the concurrent version was Lightroom 4 , followed later by Lightroom 5 and finally Lightroom 6 . The Evolution of Lightroom: From Lightroom 4 to Lightroom 6
To understand the era of what users call "Lightroom CS6," it is helpful to look at the transition from perpetual licenses to the subscription-based Creative Cloud: Lightroom vs Photoshop cs6 - Adobe Community adobe lightroom cs6