I moonlight behind an LLC for exactly this reason. I got an F500 client a long time ago and I was nervous that they'd figure out that my Sole Proprietorship was

I moonlight behind an LLC for exactly this reason. I got an F500 client a long time ago and I was nervous that they'd figure out that my Sole Proprietorship was just me (don't even remember why I thought that), so one night I went to the Secretary of State website and registered an LLC and once that was done, got a tax EIN from the IRS. Completely unnecessary at the time, it turned out, but over the years I've found that a lot of people are more comfortable working with Joe Blow LLC than just Joe Blow.