A handful of companies collect almost all of it.
Federal contracting looks like a broad market and behaves like a short list. Of the 1,113 public companies in the data, the top 10 take 66% of the $3.04T in attributed obligations, and the top 25 take 85%. More than a thousand other issuers split what is left. Lockheed Martin alone ($595B) earns more than the bottom ~1,000 combined.