IBM — not Microsoft, Google or OpenAI — tops the list of firms with the most AI-related U.S. patent applications over the last five years, according to research shared first with Axios.

Why it matters: While patents are just one indicator of research intensity, the increase in the total volume of  AI-related patent applications indicates strong interest, especially among large tech companies — and IBM's lead could show that its AI push is more than just marketing.

According to an analysis by IFI Claims, IBM made 1,591 AI-related patent applications, followed by Google, Microsoft, Samsung, Intel and Adobe, Capital One and China's Baidu.

• More than one in five, or 22%, of the AI-related patents dealt with generative AI.
• GenAI patents are rising quickly, IFI Claims said, with granted applications growing at a compound annual rate of 16% over the past five years. while patent applications for the field have  grown at a rate of 31%.

How it works: IFI Claims, which specializes in patent data, created a system to identify AI and generative AI-related patent filings.

• The company noted that with newer technologies, patent classifications take time to emerge.
• "The patent coding system often trails state-of-the-art technologies; as a result, they are assigned more general classifications," it said. "IFI tailored a query that used technologies currently in play for GenAI. As time goes on, the classifications will enlarge."

Between the lines: ChatGPT creator and AI pioneer OpenAI didn't even make the top 25 companies on the list. IFI Claims said it found just one patent application, which only recently became public.

• "This is surprising for an organization that is knowledge-based," IFI said.
• However, it noted that the company may have more recent filings that have not yet been made public.
• Or, IFI suggested, OpenAI could be more focused on protecting its intellectual property via trade secrets rather than patent filings, which are eventually made public.
• OpenAI declined to comment to Axios on its approach to patents.

Yes, but: Patents are just one measure of innovation. Not all companies focus on getting that type of protection for their innovations,and not all patent applications are granted.

• Also, there are no guarantees that a patented invention will ever become a feature or product.

The big picture: IBM had long been the overall leader when it comes to U.S. patents, but Samsung has topped the list the past two years for most U.S. patent awards.

• This year Qualcomm finished No. 2, becoming the first American company in the last three decades to top IBM.

IBM has said it will take a more selective approach to patenting, focusing on key areas rather than patenting all its inventions.

• AI is one of the areas it has cited.

Of note: IBM's generative AI patents are split across image, speech, text and video, as are those from Google and Samsung.

• By contrast, Nvidia's patents mostly focus on images and video, while Apple's are centered on speech.

What to watch: Every one of these patents is for a human-made invention relating to AI. But one of the big emerging questions is how to handle inventions produced by AI itself as the technology advances.

• Generative AI is aiding the search for new materials and formulas for everything from batteries to medications.
• But the law hasn't yet settled on how to treat AI-generated inventions — and most forms of intellectual property protection require a human to have created the work.

What they're saying: "This focused approach to patenting is also complementary with our commitment to open innovation, including in AI," IBM said in a statement. "Our watsonx platform, for example, is built on both patented and open source technologies."