The publisher logo appears on all the title pages if you have one set for the overall book. If you prefer not to have the publisher logo on the title page, you can customize it by either replacing it with a full-page image or a standard chapter page.
Replace it with a Full Page Image
Click the Title Page in the left navigation pane
Since the newest update, you'll see a link near the top of that page that says Convert to Full Page Image
This option will give you the most flexibility to insert a full page image or a designed image of your book cover
Replace it with a standard chapter page
Delete the auto generated title page (click the little x beside the title when you hover over it)
Click add a New Chapter and replace the title and subtitle information with your book or part details.