I heard Lightroom 6 was a direct upgrade from 5, so Do I need to have 5 first in order to upgrade to 6. I currently operate on Lightroom 3.
You can upgrade to Lightroom 6 from version 3, at time of purchase select the base product as Lightroom 3.
When you install Lightroom 6 on your system you need to have the serial number for Lightroom 3 with you in order complete the activation.
Refer:Download and install Adobe Lightroom 6 (Single App license)
Hope that helps.
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