: If you've lost your serial number, you can try contacting Sony's customer support or the support team at Magix (as they've acquired the audio product line from Sony). They might be able to help you recover your serial number.
Unfortunately, I couldn't find any reliable sources offering free serial numbers for Sony Sound Forge 12.6. Using unauthorized or cracked software can pose security risks and may not provide the best performance. sony sound forge 126 serial number free