Forest Carbon Sequestration Patents

One great way to deal with the climate crisis we're in the middle of right now would be to move some greenhouse gasses from the atmosphere to somewhere else, perhaps the geosphere. We call that carbon sequestration. Plants are real heroes because they do this every moment of every day.

Some of us humans are pretty clever, and maybe we can use plants' ability to take atmospheric carbon and stitch it into their tissues to our advantage. That's the subject of a patent and two patent applications I want to share with you. The inventor behind the patents is Ning Zeng, a professor at the University of Maryland in the Department of Atmospheric and Oceanic Science.

Professor Zeng filed a patent application which was published in 2010 titled Carbon sequestration via wood burial and storage (number 20100145716). The basic idea for the invention is to take wood and bury it beneath soil so that there isn't enough oxygen for it to decompose. Alternatively, the application proposed to store wood in warehouses. This ought to be patent eligible subject matter, in that the application proposes a process for sequestering carbon. Now, abstract ideas are not patentable subject matter. But since the application includes ways to put the abstract idea of carbon sequestration into practice by putting wood someplace where it can't decompose, and therefore the carbon takes a long time to return to the atmosphere, the examiner considered more than just the subject matter for this application.

Nevertheless, this application was abandoned for failure to respond to an office action. The action was a Final Rejection, and the most difficult part of that rejection was a rejection for obviousness. The basis of the obviousness rejection was that it would have been obvious at the time for a person of ordinary skill in the art to combine what was already known in the field and then think to bury wood to prevent it from decomposing. Getting past this sort of obviousness rejection is an important consideration for an inventor, and a great reason to hire a skilled patent practitioner.

By the way, I am a registered patent agent, in case you happen to be looking for help with your patent application. Keep in mind though that I'm not a lawyer, so nothing in this post is legal advice in any way. And also just reading my posts or website does not enter us into a client relationship. If you're interested in working with me, please don't hesitate to reach out. But you'll have to do more than read my blog posts to be my client!

Now Professor Zeng has a published, pending patent application for similar but modified inventions. Method and system for wood harvest and storage, carbon sequestration and carbon management was published in June of last year (number 20250209471). Beyond the proposals of the '716 application, now the inventor is also suggesting several other methods to sequester carbon. These include:

• burying the logs in mud or concrete

• making small woody debris into biochar and using that to fill in gaps between logs

• using the logs as foundation materials for construction

• using logs to build up seawalls to protect low-lying areas from sea level rise due to climate change

I'm curious to see if this application elicits any obviousness rejections from the Examiner. The application is still early in the review process. It was filed on December 25th, 2024. A couple things to note there. First, I feel badly for the patent practitioner who is sending in patent applications on Christmas Day. I strive for better work-life balance than that. Second, for those who don't know, it can take a long time from filing to issuance. The average time for a utility patent from the United States Patent Office (USPTO) is about 25-30 months, with many utility patents taking longer than three years before they issue. I'll keep an eye on this application as it moves through examination. It's filled with good ideas, but it remains to be seen whether the USPTO thinks the applications of those ideas as described in the application are patentable.

The USPTO issued a patent (number 12198146) to Professor Zeng in January of 2025 for processes stemming from part of the basic idea behind these inventions. Those are the process of selecting wood for storage, and balancing the costs and benefits of the storage in what the patent calls "wood vaults," which may be above-ground or below-ground. The issued '146 patent contains clear applications which are not intuitive. It's less clear to me if the '471 application will clear the obviousness hurdle, but I will keep an eye on it.