@KittyM, in the instructions of IRS form W-9 on page 5 under the chart "What Name and Number to Give the Requester":
For #6. Sole proprietorship or disregarded entity owned by an individual, the chart says to provide "The owner".
There's a footer reference (3) with the following:
You must show your individual name and you may also enter your business or DBA name on the “Business name/disregarded entity” name line. You may use either your SSN or EIN (if you have one), but the IRS encourages you to use your SSN.
For #8. Disregarded entity not owned by an individual, the chart says to provide "The owner".
