Drug companies patent their drugs so they have exclusive rights to manufacture the drug.  These patents expire after a given amount of time, and then generics may be manufactured. 

• To determine if there is still a patent on your particular drug, granting the manufacturer exclusive rights to produce the drug, look up your drug in the database Orange Book: Approved Drug Products with Therapeutic Equivalence Evaluations (AKA the Orange Book). If your drug is newer than 2003, the Orange Book will also lead you to patent numbers that can be easily looked up to learn more about your dosage form and the purposes of its excipients.

These instructions are based on drugs that were approved 2003 or later. 

1. Look up your drug by proprietary name in the Orange Book
2. When the list of your drug's various strengths comes up, click on any hyperlinked Application Number

3. Note your drug's Approval Date, and then click on the hyperlink that says Patent and Exclusivity Information

4. With a drug that was approved 2003 or after, you'll likely see a list of patent numbers. The higher the patent number, the newer the patent. Sometimes an older patent during initial development is most helpful, and other times newer patents provide better details. 
5. Copy your patent numbers and place them in a document, and get ready to look them up in the U.S. Patent Office's Patent Number Search.

6. Selecting which patent to use can be tricky, particularly since the patents often don't have changes that are easily discernible. If you only have a few patent numbers, you can search on all of them to try to determine the most relevant patent.
7. Looking at the FDA Review History (see instructions on next tab) can help you determine if you've selected the right patent

For tips on selecting the correct patent, please take this quick click-through tutorial:

Your drug delivery system may also use a separately patented technology that's not part of this drug's patent history. If there is a remarkable technology, then it's often touted in the drug's webpage. If you don't have a patent number, it may be challenging to find a technology patent. Some examples of technologies not found in your drug's patent history may include:

• Inhalers
• Transdermal systems
• Devices that assist delivery

Look for these key indicators:

• Unique delivery method touted in literature/prescribing information
• Prescribing information includes references to a patent (be sure to look at the references at the end of the package insert)
• Drug monograph contains references to a patent (be sure to look at the references at the end of the monograph)

Try these options:

Need Help Searching for Patents?

Read these article to learn why you may see so many similar patents for your assigned drug.