Search-engine co-founder Anurag Acharya explains why it now tells authors when their papers should be made free to read.

Google Scholar, the popular free search engine for scholarly literature, revealed an unexpected feature on 23 March: it is keeping track of whether research papers covered by funders’ public-access mandates are free to read.

A scientist’s Google Scholar profile now displays how many of their papers should be free to read because a funder requires it; how many actually are; and how many are not. The search engine also encourages authors to make non-compliant papers public, if necessary simply by uploading them to their Google Drive. Researchers’ reactions have been mixed. Some have called it a ‘wall of shame’ and criticized it for mistakes — but others have welcomed it for prompting researchers to make their papers public.

Anurag Acharya, the co-founder of Google Scholar, explained to Nature how the tracking works — and how it might change in the future.