In a statement to Motherboard, Adobe confirmed the letter's authenticity, but wouldn’t provide any additional detail beyond what was included in the notices. Dolby’s lawsuit accused Adobe of copyright violations related to how the licensing costs Adobe paid to Dolby would be calculated under this new model. In a controversial move, Adobe pivoted away from the standard software model to the cloud-based subscription model in 2013, resulting in notably higher revenues (and higher prices for customers).

]( src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1126905276693667841&refurl=https%3A%2F%%2Farticles%2F19%2F05%2F13%2Fadobe-warning-of-legal-problems-if-users-keep-using-old-versions-of-creative-cloud-apps)The company didn’t inform users why they needed to discontinue use of the software, but the company’s Twitter account indicated the issue stems from “ongoing litigation.” AppleInsider, which first reported the notices, pointed to a copyright lawsuit filed last year by Dolby Labs.

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