To look up all patents and trademarks held BY COMPANY in LexisNexis:
1) Click the SEARCH BY CONTENT TYPE then the COMPANIES tab, 2) look up your company in COMPANY DOSSIER and then 3) patents is on the left side of screen
You can also search patents in general in LexisNexis. Again, select By Content Type then Patents.
Or, you can use the US Patent Office website, but you can’t search by company so well. They also have trademarks, BTW.