From https://www.thebignewsletter.com/p/monopoly-round-up-time-ba...

> Our work against algorithmic rent-fixing is starting to bear real fruit. Multiple cities have passed laws prohibiting corporate landlords from using rent-fixing software, including San Francisco, San Diego, Seattle, Philadelphia, and Providence, RI. These laws aren’t complex and don’t require unwieldy market definition, you just have to show that the defendant is using nonpublic information in an algorithm to set prices. And they are being enforced, with six different lawsuits now pending.

Will they just stop using an ‘algorithm’ and have a mathematician sit there and state numbers that are of unknown origin?

Can you elaborate on what is meant by “rent-fixing”?

A bunch of landlords all use the same software to tell them how to price rents. The software continually pushes prices higher and higher. The software requires landlords to use their pricing as a condition of use. Now you have a price-fixing cartel for rent.

Like "price fixing". Landlords illegally colluding to artificially inflate the price of housing.