CTB/McGraw-Hill, Monterey, CA – owns itself

Riverside Publishing, Itasca, Ill – owned by Houghton Mifflin Riverdeep Group PLC (Boston and Dublin, Ireland)

Harcourt, San Antonio, Texas, owned by Pearson Educational Measurement  (recently purchased from Reed Eselvier according to Pearson's website, but Ed Week 8/1/07 reported that Pearson sold Harcourt to Reed)

Pearson Educational Measurement (London, England, and various US addresses) already was a player, prior to acquisition of Harcourt.

That is, there are now 3 major commercial test publishers – Riverside, CTB and Harcourt/Pearson. ETS is far less a player in public school testing, and then there are minor testmakers and subcontractors for scoring, etc., as well as ACT for college admissions (along with ETS).

Ed Week (8/1) reported on sale of Harcourt Education (not testing) by Reed to Houghton Mifflin, which will consolidate publishing with 3 occupying 80-85% of market: Pearson, Houghton Mifflin, and McGraw Hill.
Monty Neill, Ed.D.
Co-Executive Director
FairTest