Hacker News Reader

Presumably Anthropic / Claude, OpenAI / GPT, Google DeepMind / Gemini.

thank you. yes I meant that.

Meta, OpenAI, and Anthropic come to mind.

In TFA they name OpenAI, Google DeepMind and Anthropic.

TFA = The Freaking Article; wow! what a full form.

Likely 4, based on the other comments. Maybe 5 if you want to add Midjourney.