Access to accurate and reliable insights is important for the success of any scientific intellectual property (IP) strategy, especially when it comes to navigating the chemical IP landscape. Confidently knowing which chemical structures are novel—and which ones aren't—is essential to minimize the risk of your patent claims being rejected, your competitors getting the upper hand, or even your business pouring millions of dollars into R&D, only to find your product isn't new.
To avoid these risks, your team likely looks for chemical IP that specifically matches molecules of interest—but are you missing substances that are embedded in Markush structure claims? A Markush structure is a type of generic chemical shorthand used in global patent claims to efficiently describe a group of structurally similar substances. A relatively simple Markush structure looks like this:
Markush structures vary in complexity, with some listing just a handful of specific substituents and others inventively encompassing thousands of unique structures. Here, we clarify a common misconception regarding Markush in chemical IP searches to ensure your team has a comprehensive view of the landscape when developing IP strategies.
What's missing from your chemical IP search?
There is a common misconception that all chemical patent searches based on a chemical structure include Markush structures. This misunderstanding can result in critical substance disclosures being overlooked, leaving gaps in your view of the relevant IP landscape that can lead to missed opportunities and risks. For example, consider the following structural description of a group of molecules that might be of interest, where Cb is any carbocyclic group and Ak is any unsubstituted carbon chain:
A generic chemical structure query such as this could represent thousands of potential specifically disclosed substances. However, using SciFindern to search for specific compounds matching this generic query uncovers no mentions of any such substances in published journal articles, patents, catalogs, etc. Great news, your compounds appear to be completely novel! But are they?
This is where the confusion arises. Though the query we used is generic (i.e., represents many potential specific substances), and looks like the Markush representations in patents, we have not really searched the Markush structures in patents yet. A broad generic query, searched against a database of specific chemical substances, will only return answers that disclose a matching specific chemical structure. It won't identify patents covering relevant areas of chemical space protected by patented Markush structures, which could lead to poorly informed business decisions. This common misconception is compounded by the fact that some search platforms describe generic structure search as Markush search on the basis of the query being Markush in nature.
The Markush truth: How to find what you are missing
The key difference between a generic chemical structure search and a search of patent Markush structures lies not in the query itself, but in the data collection the search is querying against. To find patent Markush structures, the platform must have access to a searchable collection of patent Markush data. Such data collections are labor-intensive to develop, as the Markush structures must be broken down into the searchable component parts and connections. This requires a high level of human chemical expertise, as well as specialized database and search technology. For this reason, most search platforms, even some specializing in chemistry, do not contain this data.
Going back to our example, when we add Markush search to the scope of our SciFindern query, we find two additional patents that are clear matches to our molecules of interest and likely relevant to our IP strategy:
Using PatentPak, we can go straight to the specific relevant claim in the full text of the granted patent in two clicks. While missing two relevant patents might not seem to be a big deal, in reality it can make or break your IP strategy and cost an organization millions in wasted resources or worse, legal fees. Thus, using an IP search platform or service that supports a complete chemical IP search is essential.
For a comprehensive view of the chemical IP landscape, look no further than CAS
The CAS content collection is one of the few sources for searchable global patent Markush disclosures. It contains over 1.2 million searchable Markush structures covered in patents from 1988 to the present and is updated daily. SciFindern from CAS is the only platform that makes specific chemical structure searching and true Markush searching, as well as reaction and reference searching, available in a single end-user interface. Alternatively, STN provides IP professionals with an advanced interface to these datasets. Custom alerts are also available to help you stay up-to-date when new information matching your query of interest is published.
Even with these tools, ensuring that your chemical IP search is airtight can be a challenge. Thus, it may be valuable at critical decision points to have a professional search performed by the experts at Science IP, the official research service of CAS. Knowledgeable experts can search all relevant databases and give you peace of mind that you have the complete IP picture, minimizing risk and maximizing opportunity in your IP strategy. Learn how CAS can help.
