While testifying in court, the Meta CEO said WhatsApp and Instagram probably wouldn’t have been successful on their own.

The trial between the US Federal Trade Commission and Meta began this week—and the future of the company is at stake. The FTC wants Meta to sell off two prized assets, Instagram and WhatsApp, arguing that it acquired them illegally to suppress competition.

Meta’s antitrust trial, in which the government contends the company killed competition by buying young rivals, hinges on unknowable alternate versions of Silicon Valley history.