How does claiming foreign priority affect the prior art date in my application?

Claiming foreign priority can significantly affect the prior art date in your application:

• For applications subject to pre-AIA law, the foreign priority date becomes the effective U.S. filing date for prior art purposes under 35 U.S.C. 102(a), (b), and (d)
• For applications subject to AIA law, the foreign priority date is treated as the effective filing date for prior art purposes under 35 U.S.C. 102(a)(1) and (a)(2)

This means that intervening disclosures between your foreign filing date and your U.S. filing date may not be considered prior art against your application. However, it’s important to note that the claimed subject matter must be fully supported by the foreign application to get the benefit of its filing date. Additionally, the priority claim must be proper and timely made for this benefit to apply.