One of China’s leading AI labs has claimed the cow — aka the mysterious Ox Alpha model — and Chinese fans couldn’t be happier.
In a Wednesday blog post, Z.ai said Ox Alpha had been a free-to-use preview of its new GLM-5.3-Flash model. The model had appeared on OpenRouter and OpenCode on August 20, but no one claimed it for days — sparking spirited debates online about which lab had dropped it.
“Before release, we tested GLM-5.3-Flash anonymously as ox-alpha on OpenCode and OpenRouter to gather user feedback,” the company wrote in its blog post. “It quickly became the most popular model of the week — with all of this traffic served on Chinese AI chips.”
Users on the Chinese social media platform Weibo, the country’s version of X, rejoiced at the announcement. As of noon on Thursday, a hashtag about Z.ai claiming ownership of Ox Alpha had thousands of posts under it, and was ranked among the top 20 hot topics on the platform. It had been viewed more than 13 million times in under 24 hours.
One user whose location was listed as Beijing said the model is amazing, delivering strong performance at a low cost. Another in Chongqing said that Ox Alpha’s significance shows that Chinese open-source models have taken another step forward in the global developer market.
A user posting from Sichuan province lauded Z.ai for using domestically produced chips, saying that the example shows that Chinese chips can efficiently support large-scale AI use. Another poster from Sichuan called the model “ridiculously cheap.”
It’s not just internet users in China who have praised the model; executives in the US have, too. Stripe CEO Patrick Collison said on X that he tried the model and found it “very impressive.”
Chinese internet users have been laser-focused on Ox Alpha since the model debuted last week — and all the mystery has come with a touch of humor, too. Over the weekend, Weibo users nicknamed the model “Niu Lai,” the title of a Chinese animated movie released in August that sparked a mass of memes online in the country.
GLM-5.3-Flash is the latest Chinese AI model to make a splash beyond China. Another recent example is Chinese AI lab Moonshot AI, which launched Kimi K3 in July, an open-weight model that rivals the capabilities of models from OpenAI and Anthropic at a lower cost.
And Alibaba released its latest Qwen3.8-Flash-Next model on Wednesday, an efficiency-focused, open-weight model that promises lower training and inference costs.
Weibo users have historically heaped praise on Chinese AI labs making breakthroughs in the West. For instance, when Kimi K3 was having its moment in July, users called Moonshot AI’s founder, Yang Zhilin, a “millennial genius,” with some even commenting on his youthful “baby face.”
