Google Disavow is the best option now days to remove the bad or spammy link which are thrown to your website by your competitor's or others.
This is entirely false if you properly follow the instructions before using the disavow tool and then correctly create the file (with proper comments). Google penalties are largely algorithmic, rarely manual, and only a few highly aggressive tactics may ban a domain for life. Google created the tool partly to help prevent negative SEO. Google is not out there to destroy webmasters who hired someone and the person/company uses a technique that violates their webmaster guidelines (unknowingly to you uses such strategy).