Full Idea
The semantic content of a sentence is not the set of circumstances supporting its truth. It is rather the semantic content of a structured proposition the constituents of which are the semantic contents of the constituents of the sentence.
Gist of Idea
Semantic content is a proposition made of sentence constituents (not some set of circumstances)
Source
Scott Soames (Why Propositions Aren't Truth-Supporting Circumstance [2008], p.74)
Book Reference
Soames,Scott: 'Philosophical Essays 2:Significance of Language' [Princeton 2009], p.74
A Reaction
I'm not sure I get this, but while I like the truth-conditions view, I am suspicious of any proposal that the semantic content of something is some actual physical ingredients of the world. Meanings aren't sticks and stones.