ABBYY no longer sells FineReader 12 directly, as it has been succeeded by FineReader PDF 15, 16, and now ABBYY FineReader 18. However, here are legal options:
On your computer, license information is often stored in C:\ProgramData\ABBYY\FineReader\12\Licenses (note: this folder may be hidden). Activating the Software Abbyy Finereader 12 Professional Serial Number