For this chain-of-thought reasoning and answer, what was the question?
To answer this question, we should know that: Goldfarb v. Virginia State Bar, 421 U.S. 773 (1975), was a U.S. Supreme Court decision.
A: U.S. Supreme Court
Q: Goldfarb v. Virginia State Bar, 421 U.S. 773 (1975), was a U.S. Supreme Court decision. It stated that lawyers engage in "trade or commerce" and hence ended the legal profession's exemption from antitrust laws.

Based on this passage, the goldfarb v. virginia state bar decision on anti-trust laws was decided at what level?