Tate & Lyle Lessons: Is Your Patent Enforceable? Are Your Methods Detectable?

Sarah Hill's "Patent Debate Rumbles on after Tate & Lyle Sucralose Ruling" reminds us of the many pitfalls that inventors and patent holders face. While sucralose the molecule has been around for a while, the methods for efficiently making commercial grade sucralose are much newer and are the subject of patents by British giant Tate and Lyle. The problem with process patents - such as Tate and Lyle's patents on the method of making sucralose - is that they are often difficult to enforce. Competitors may be tempted to infringe in secret and sell in public, claiming that a different process was used. That's what happened with Tate & Lyle. Chinese companies produced a similar product but claimed they were using a novel process they invented. Lacking any published IP to show that they had conducted their own R&D and invented their own techniques, the Chinese company, according to Tate & Lyle, more likely was simply copying T&L's patent. But the Chinese company prevailed by claiming it was a new process protected as a trade secret.

Chemists knows that a different process can mean different trace amounts of byproducts, but the chemical fingerprint of products made within the scope of the claimed invention is often overlooked when patents are filed, and perhaps even when litigated. It can be quite expensive to do chemical forensics to link a process to a particular method when there may be many possibilities to consider. I suspect that the most cost-effective time to consider chemical fingerprints as indicators of infringement is when the experimental work is being conducted that leads to the patent.

The inventors and the R&D team should be concerned with enforceability and detection, and the issues should be covered as part of their training in your company or university, so they can consider ways to build in additional enforceability in the patent. For example, if the method to be claimed will generally result in trace amounts of zinc in the product, then mention that and include some product-by-process claims (e.g., a sweetener solution made according to Claim 1, having at least 5 ppm zinc). Such information and claims could strengthen the position of the patent holder. Whether that helps or not depends on the details of the process and the uniqueness of the chemical composition, but it's something the inventors should be thinking about as they do experimental work and especially as they begin preparing for a ptent. Is the patent enforceable? Is there anything unique about the process that will show up in the properties of the final product? Any tell-tale signs of potential infringement that we can build into the patent? Put it in the patent itself. With opportunities for detection of infringement built into the patent, it can help deter deliberate infringers and increase your odds of success.

Maybe just signaling that you've considered chemical forensics in creating your process will help deter copyists.