Hong Kong, Dec 4 : ChatGPT developer OpenAI has reportedly applied for 'GPT-6' and 'GPT-7' trademarks in China as Sam Altman-run company continues to build large language models (LLMs). The company has submitted two Chinese trademark applications for GPT-6 and two other filings for GPT-7, South China Morning Post reported, citing records of the Trademark Office of the China National Intellectual Property Administration. The applications were submitted by OpenAI OpCo, the company's entity in China. None of OpenAI's services are available in China, including Hong Kong, at the moment. OpenAI did not comment on the report. Since the launch of ChatGPT a year ago, OpenAI has been advancing the capabilities of its deep learning LLMs. ChatGPT was initially built on GPT-3.5, which has 175 billion parameters. Altman, the creator of AI chatbot ChatGPT who is now back at the helm after an intense drama over his ouster as CEO, had said that the company was not presently training GPT5 -- the successor to GPT4. Earlier this month, ChatGPT reached 100 million weekly active users and the company released new GPT-4 Turbo model that is more capable, cheaper and supports a 128K context window. Addressing the company's first developer conference, Altman said over two million developers use ChatGPT, including more than 92 per cent of Fortune 500 companies. GPT-4 Turbo has a 128k context window so it can fit the equivalent of more than 300 pages of text in a single prompt. 'We also optimised its performance so we are able to offer GPT-4 Turbo at a 3x cheaper price for input tokens and a 2x cheaper price for output tokens compared to GPT-4,' said the company. In addition to GPT-4 Turbo, the company is also releasing a new version of GPT-3.5 Turbo that supports a 16K context window by default. OpenAI also released Assistants API to help developers build agent-like experiences within their own applications. /IANS