You should also investigate the current Knowledge Graph entries that are related to your industry, and work to become associated with recognized companies or entities in that industry. This could be from links or citations on the entity websites, but it can also include being linked by third-party lists that give industry-specific advice and recommendations, such as being listed among the top competitors in your industry ("Best Plumbers in Denver," "Best Shoe Deals on the Web," or "Top 15 Best Reality TV Shows"). Links from these posts also help but are not required — especially if you can get your company name on enough lists with the other top players. Verify that any links or citations from authoritative third-party sites like Wikipedia, Better Business Bureau, industry directories, and lists are all pointing to live, active, relevant pages on the site, and not going through a 301 redirect.
While this is just speculation and not a proven SEO strategy, you might also want to make sure that your domain is correctly classified in Google’s records by checking the industries that it is associated with. You can do so in Google’s MarketFinder tool. Make updates or recommend new categories as necessary. Then, look into the filters and relationships that are given as part of Knowledge Graph entries and make sure you are using the topic and filter words as keywords on your site.