General Motors is trying to persuade lawmakers across the country to approve rules that would benefit the automaker while potentially keeping its competitors off the road.

The carmaker denies trying to freeze out other brands, but legislators in four states say GM lobbyists asked them to sponsor bills that the company’s competitors contend would do just that. The bills set a blueprint for the introduction of fully self-driving cars that are part of on-demand, ride-sharing fleets, but they must be owned by an automaker.

Competitors working on self-driving technology like Uber and Alphabet’s Waymo fear the measures could shut out their companies because they don’t manufacture cars. And some automakers that are developing autonomous cars say they could be shut out, too, because their vehicles still rely on having a driver ready to step in.

GM began by getting a bill passed last year on its home turf, in Michigan. In response to complaints from Waymo, a compromise bill was also passed to allow participation by technology companies.

This year, bills similar to the Michigan law, but without the compromise language, have been introduced in at least five states: Georgia, Illinois, Maryland, Massachusetts and Tennessee. GM lobbyists have also urged lawmakers in other states to introduce versions of the bill.

Arizona lawmakers met last month with Gov. Doug Ducey’s staff, GM, Waymo, Uber, Lyft and other companies in response to GM’s effort to get a bill introduced there, said state Sen. Bob Worsley, R-Mesa.

Prospects for passage of the bills are uncertain.