In the brilliant film The Social Network, the curious mentor/mentee relationship between Mark Zuckerberg and Napster cofounder Sean Parker is explored. Seeking advice on the direction and trajectory of the still fledgling website, the pair—along with partner Eduardo Saverin—discusses the pros and cons of advertisements on Facebook during a lunch meeting.

“A million dollars isn’t cool; you know what’s cool?” Parker quipped.

“…A billion dollars.”

We all know how much heavier Zuckerberg’s pockets have gotten since that meeting. We also know how the company’s view of advertising has evolved, as well.

Facebook avoided advertising altogether in its infancy—but it’s become an ad-machine in recent years. There’s advertising on the website’s sidebars. There’s auto-populated sponsored content. And now it looks like Facebook is considering adding advertising functionality into its messaging client.

This is a big leap for Facebook—but don’t immediately jump to delete messenger or get paranoid that some unseen developer is lurking your private conversations. Per leaked internal documents, it appears that Facebook’s first step for in-message ads will be limited to conversations directly with businesses. What this seems to entail is that the new message you receive may be from a corporate bot trying to sell you loofahs.

Facebook’s relationship with advertisers has changed rapidly over the years, and this is yet another domino to fall toward enhanced and increased ads. Is this where it stops? We shall see—but when there’s billions to be made, there’s always a new avenue to deepening ones’ pockets.