The US Trademark Office rejected the application, deeming "GPT" merely descriptive of the features, functions, or characteristics of OpenAI's goods and services. The decision was based on extensive evidence showing "GPT" is widely used in the industry to refer to a specific type of AI technology, making it not distinctive enough for trademark protection under the Trademark Act Section 2(e)(1). Additionally, OpenAI's application was partially refused for Class 09 due to unacceptable specimens, as they did not demonstrate the mark's use in commerce in a manner that allows for the downloading or purchasing of the software.
Also: I understand the trademark decision but does OpenAI have any patents on GPT? Google has for example patented word2vec, https://patents.google.com/patent/US9037464B1/en