I read a sci-fi story with this premise. Companies could only be as large as X before starting to pay prohibitively large taxes in order to stay 'for profit en

I read a sci-fi story with this premise. Companies could only be as large as X before starting to pay prohibitively large taxes in order to stay 'for profit entities' or become companies devoted to the public good. So you'd end up with large telecoms who were non-profits dedicated to improving the level of global interconnectivity, and lots and lots of tiny 2-10 man companies that did research or sales.