X, the former Twitter, updated its recommendation algorithm on Tuesday night (25) to stop suggesting profiles of registered candidates to users who do not follow them, after spending the first ten days of Brazil's election campaign in violation of a rule set by the TSE, the country's Superior Electoral Court, which regulates elections. The change came after questions from the newspaper Folha de S.Paulo, which found, together with an analysis by the organization Sleeping Giants Brasil, that the platform's filter missed at least 1,442 candidate accounts.
The TSE rule bars social networks from including profiles declared by candidates in their content recommendation systems during the campaign, which began on August 16. In practice, the platform cannot show a candidate's post to someone who does not follow that account. Think of the recommendation algorithm as a shop window: following a profile is like walking into the store on your own, while a recommendation is the product the shopkeeper puts in the window for passersby. Under the election rules, candidate content cannot go in the window. The only exception is paid boosted posts.
On August 14, X announced it would apply the rule and, citing transparency, published the document with the list of accounts the filter would cover. By Tuesday afternoon the list had 665 profiles. Campaigns, however, had declared more than 2,107 X accounts to the TSE, according to Folha's analysis. That left at least 1,442 candidate profiles, from different parties, outside the filter and eligible to be recommended to any user. Folha says it saw several of them being recommended while browsing the platform.
After the newsroom contacted the company, the filtered list jumped to nearly 2,400 accounts that same night, and Folha says it no longer found candidate recommendations. Still, there was a window of unequal treatment: candidates filtered from the start of the campaign lost reach that rivals kept for at least ten days.
The case lays bare the incentives at play. Recommendation is the attention engine, and the ad revenue engine, of networks like X: the more the platform pushes content to non-followers, the more screen time and the more ads. The rule's exception, paid boosting, is itself a revenue stream. History also weighs: in 2024, X was suspended in Brazil for nearly 40 days for defying Supreme Court orders, and complying with electoral rules is cheaper than risking a new clash with the courts in one of its largest markets.
What we still do not know
It is unclear why the initial list was so much smaller than the universe of declared accounts, whether because of a technical failure or the criteria the company used to build the filter. It is also unknown how many views the unfiltered profiles racked up in that period, or whether the TSE will open an inquiry or apply any sanction.
What to watch: the court's reaction, which may include a formal demand for explanations, and the filtered account list, which X itself published and which campaigns can check to confirm their profiles are on it. If your timeline still recommends a candidate's account you do not follow, the filter still has holes.