Blum is a legal activist who organized the lawsuits that led the U.S. Supreme Court to end race-conscious college admissions in Students for Fair Admissions v. Harvard (2023).

He founded the Project on Fair Representation in 2005 and Students for Fair Admissions in 2014.

• He also organized Shelby County v. Holder (2013), in which the Supreme Court struck down the coverage formula of the Voting Rights Act of 1965.

• In 2023, he founded the American Alliance for Equal Rights, which has sued organizations over race-based grant and fellowship programs.

• He previously worked as a stockbroker.