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Claiming Foreign Priority in US Patents

As an inventor, you may have filed a patent application in a foreign country before filing in the United States. If this is the case, you may be eligible to claim foreign priority in your US patent application. This means that you can claim the benefit of the filing date of your earlier foreign patent application when you file your US patent application.

Why is this important?

Claiming foreign priority can help you secure your invention in the US faster. It also enables you to take advantage of the first-to-file system in the US, which gives the first person to file a patent application the right to obtain a patent. By claiming foreign priority, you are effectively establishing that you were the first to file for your invention in a foreign country, which could give you an advantage over other inventors who may file similar applications in the US later.

How to claim foreign priority in the US

To claim foreign priority, you must file a formal declaration in your US patent application, specifying the foreign application and its filing date. This declaration must be filed within one year of the filing date of your foreign application. It is essential to note that you must also pay the appropriate fees to the US Patent and Trademark Office (USPTO) to claim foreign priority.

When making a foreign priority claim, you must also ensure that the US patent application corresponds to your foreign application. This means that the US application should include the same or substantially the same invention as your foreign application. If the USPTO determines that your US application does not correspond to your foreign application, it may reject your foreign priority claim.

What to keep in mind when claiming foreign priority

When claiming foreign priority, it is vital to be aware of the following:

  1. Time limits – For a utility patent, you must file a foreign priority claim within twelve months of the earliest priority date claimed. A design patent application must include a foreign priority claim within six months of the filing date of the first foreign application.

  2. Correspondence – Your US patent application must correspond to your foreign application.

  3. Fees – You must pay the appropriate fees to the USPTO to claim foreign priority.

  4. Patentability – Your invention must still be patentable in the US, even if it was granted a patent in a foreign country.

Claiming foreign priority can be a complex process, and consulting with a patent attorney is recommended to ensure that your claim is handled correctly. Your patent attorney can help you navigate the foreign priority process and advise you on the best strategies for securing your invention in the US.


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