Example:

Q: I need to file 2010-2021(01/01-12/31) for one corporation. Do I need 12 different licenses to do these files for 1 corporation? Or is it one license per corporation?

A: You can choose the following 4 versions to file all your tax returns, please see the screenshot below. Since license key works in one version only, you would purchase a 5-tax-return license key of 2021.2, a 5-tax-return license key of 2018.2, a 5-tax-return license key of 2015.2 and a 5-tax-return license key of 2012.2.

For example, 2021.2 version license key works in 2021.2 version only. The version supports 2019/01/01 - 2022/05/31, so tax year start and end of the tax returns must fall within that date range. It means you can prepare 3 full tax year returns in the version and need 3 licenses (2-tax-return license key + additional license key) or one 5-tax-return license key of 2021.2 (they are the same price).

Same things are for multiple corporations or forms (RC4649, T1135, etc), just purchase extra licenses for the tax returns or forms.