Over the weekend, President Obama weighed in on the famous Apple vs. Samsung patent disputes by vetoing an import ban proposed by the International Trade Commission that would have prevented Apple from bringing iOS devices older than the iPhone 4S and iPad 3 into the country.

An avowed fan of Apple’s products, it was the first time a U.S. presidential administration had vetoed a product ban by the ITC since 1987, and seemed to signal that the Obama Administration was not going to penalize an American company like Apple in favor of a foreign company like Samsung.

Financial Markets took notice. Samsung’s market cap is down a billion dollars since the vetoing.

All Things D reports:

Early Monday, South Korea’s biggest company by market capitalization fell 0.6% to 1,278,000 won ($1,137), wiping out $1.05 billion of Samsung’s market capitalization.

Washington’s decision dealt a blow to Samsung, Apple’s top smartphone competitor, just as it is seeking to expand its footprint in the U.S. market.

Ironically, the International Trade Commission is set to vote Friday on the other side of the matter: whetger or not certain Galaxy devices should be banned from import into the United States, following a patent violation complaint by Apple. If it passes, would Obama veto that ban too? Something tells me no.

• SourceAll Things D