Is it legal for a company to tow a car...?

Is it legal for a company to tow a car that is parked in their parking lot but is located in a public shopping center? I won't say any names but I used to work for a company that had their business located next to other shops. They told us in orientation that if a car without one of their stickers in the windshield is in their parking lot they would tow it. I thought that because it was in a public shopping center they couldn't do that. And they didn't mean if it was left there over night. They patrol the parking lot on an hourly basis checking windshields for stickers. It didn't affect me either way but I was curious of anyone knew the answer.

There are no signs letting people know their car will be towed.

Yes, if they are legally allocated certain parking spots in the shopping center. There is no such thing as a "public" shopping center - "public" meaning the same thing as a "public" sidewalk. A public shopping center only means it is a shopping center that is open to the public - not that it is publicly owned.

If the shopping center lease allocates a specific parking area to that business, then the business can tow vehicles that illegally park (but the area must be marked to let the public know they could be towed without the proper sticker).

Yes. It's their parking lot, people who park on their property (property they paid for) are doing so illegally, towing is fine, the end.

If it is their parking lot and it is clearly posted that your car will be towed if you park there, they can legally tow your car.

If its private property yes if its public property no.

I would have to know more about the shopping center. Who owns the parking lot? Does the buisness pay rent based on parking lot space? Are there markers denoting parking for company X company Y and such? There are a lot of different factors to it.

There are so many illegal violations against this Company they should be shut down. Approach each shop owner with your complaint. If the shop owner does not have a written contract with this Company then turn them into the City where it is located. The same thing happened in Colorado with Carelli& Carellli. They lost their contract with the City of Denver and went broke soon afterwards.