Spirit Airlines may have declared bankruptcy this spring, but the budget carrier is still worth something—to AI giants, at least. In mid-August, Google won a $10 million bid to purchase some 34 years of the airline’s data, from invoices and flight operations information to Wi-Fi sales, employee records, and crew pairings.

In a statement, a Google spokesperson said the data ‘can be helpful in improving our products and AI models.’ The sale would not include customer data, and Google ‘will not receive any personal information from this dataset,’ the spokesperson said. The winning offer, chosen over a competing $7.5 million proposal from AI data and training company Mercor, has to be approved by a judge.

If former Spirit Airlines attendants have their way, that won’t happen easily. Just days after the court announced Google’s winning bid, the labor union representing 5,500 former Spirit Airlines flight attendants filed an objection to the sale. Lawyers for the 55,000-member Association of Flight Attendants (AFA) argue the sale would include an enormous amount of sensitive employee information, and that even Google’s promised safeguards wouldn’t prevent privacy violations.

The legal objection opens a potential new front in the AI data wars, as major frontier labs including Google, OpenAI, Anthropic, and Mercor scramble to find new sources of data to help train their products. US laws have contemplated how best to protect consumer data, even after companies go bankrupt and are sold off for parts—laws that have taken on new salience and value in the age of AI.

The Spirit Airlines’ flight attendants’ legal objection highlights the gap between data protections for consumers and for workers. It also marks the first public tangle between labor unions and corporations over the sale and use of employee data for AI training purposes, legal experts say.