Twitter has launched a new API (application programming interface) that gives its enterprise customers—in other words, brands—an easily searchable database of every public tweet ever tweeted.

That’s more than 500 billion tweets. They are tweets that likely reveal a lot about the people who tweeted, such as what kind of brands you favor, which sports teams you follow, and which television shows you watch, to name just a few insights. Brands can utilize this data to better market their products to you.

The tool was built by Gnip, a social data firm that Twitter acquired last year for this very purpose: to offer data and analytics to enterprise partners. Expect the move to result in more targeted tweets, potentially more direct replies from brands, and more significantly, a whole raft of behind-the-scenes examination of your tweets without you knowing about it. (That angry tweet you sent three years ago about Spirit Air may help you get more from them next time, or may come back to haunt you if you mocked unfairly.)

A social media executive, Giles Palmer, CEO of the firm Brandwatch, told Wired that the move by Twitter means, “the dream of mining this data for real-time, in-depth, unbiased insights on a global scale is getting ever closer.” It remains to be seen whether the new API will be a dream for consumers, though.