What is the difference between a foreign priority claim and a domestic benefit claim?

Foreign priority claims and domestic benefit claims are two different ways of claiming the benefit of an earlier filing date:

• Foreign priority claims (under 35 U.S.C. 119(a)-(d)) are based on earlier applications filed in foreign countries
• Domestic benefit claims can be to earlier U.S. provisional (35 U.S.C. 119(e)) or nonprovisional (35 U.S.C. 120) applications

Key differences include:

• Time limits: 12 months for foreign priority, 12 months for provisionals, no limit for nonprovisionals
• Required documents: Certified copy needed for foreign priority, not for domestic benefit
• Effect: Foreign priority is mainly for prior art purposes, domestic benefit can confer actual pendency benefits

Both types of claims must be properly made to be effective, but the specific requirements and effects differ.