An undergraduate degree from a flagship state university often comes with a six-figure sticker price for on-campus residents. A private college could cost a quarter of a million dollars nowadays.

So since 2011, the federal government has required all schools to provide something called a net price calculator on their websites. You put in some financial data, and the calculator estimates what your actual cost would be, after any scholarships. If you aren’t among the very affluent and are applying to a private college, that net price can be tens of thousands of dollars below the list price.

Not long after the calculator became standard, a service called College Abacus emerged, allowing families to compare multiple schools at once. That spared them the laborious task of plugging the same data into multiple calculators many times over.

And how did many colleges respond? By blocking College Abacus’s access to their calculators. Imagine if Expedia or Kayak could not search for tickets on some of the most desirable airlines, and you get the idea.