MrBeast is laying the groundwork for a new business helping others with ads and marketing

Jimmy Donaldson — better known as Mr. Beast — is the biggest personality on the internet. His former manager says platforms like YouTube and TikTok are working to prevent another star breaking through in the same way.

: Weiss Eubanks/NBCUniversal via Getty Images

• MrBeast is exploring offering advertising services, according to new trademark filings.
• The top YouTuber has filed applications that list plans for a range of ad and marketing services.
• It's the latest sign of...