Of course it is legal. On the other hand, Sencha regularly pushes the license cycle by slowing/stopping bugfixes for older versions of the software. They also p

Of course it is legal. On the other hand, Sencha regularly pushes the license cycle by slowing/stopping bugfixes for older versions of the software. They also pioneered the predatory open/closed model. They are not a good company to place your trust in. Someone at Sencha decided that the value of squeezing their locked in users is more than the value of acquiring new users.