There's a "Proudly built by Commerce Guys" text and graphic at the bottom of every admin screen (when the default "Shiny" theme is selected). It's hard-coded into that theme, so ordinary users can't remove it. That's not cricket: It should be implemented as a block, to give end users more control and to keep it a community project.
(Let's face it: Virtually nobody will remove it. Still, they should have the option without branching your code.)
This is related to(for the Shiny theme itself). Regardless of what happens there, the change should be made here that can't be made there (to put it into a block). A patch is posted on that issue to remove it from the theme; others will have to implement it as a block.