They should have to sell it to another company not already vested in the cell phone business. Mergers kill competition and drive up prices (exactly the opposite of what Capitalism is supposed to do).
Just an anecdotal personal story that comes to mind....
When I moved to my current location, I signed up with a trash company. They were shortly bought out by Waste Management. Every single quarter (their billing cycle around here), it would go up a bit. After 6 years, it went from $15 a month to $23 a month. I called Republic up and they were $24 a month. Fortunately for me, there was a local trash place around here still and they were still $15 a month and had been for 8 years. In the past 5 years since switching, they went up $1. The funny thing is that Waste Management wouldn't let me off the phone when I told them I was canceling. The lady eventually got her supervisor. I honestly think she was in danger of losing her job for losing a customer. They offered me 8 months free trash removal and lowering the bill back to $15.50. I told them they would just start raising it again 4 months later and they finally canceled it. Then I read this report from the CEO on a news site about how Waste Management was going to jack up all the rates all over the country and that they might lose some customers, but they knew in most areas, they were the ONLY disposal service so people would have no choice and their overall profits would go through the roof. It did. The CEO was praised for raising profits and stock values. Waste Management is DESPISED by consumers from the things I read and it's not hard to see why. Sadly, they have a monopoly in large swath of the country. How long until they convince someone at my current trash company to sell it to them?
It's like wanting another cable service for Internet but there is nothing available. DSL isn't the same. But every time someone suggests a regulation or enforcing anti-trust laws, certain political groups have a CRAP FIT. The problem is that Capitalism doesn't work without regulation because people never do the 'right' (moral) thing. They only do what makes them the most money. Screw everyone else. They can all go to hell. It's a dog eat dog world and only the strongest (or luckiest as in where and to whom your born) survive.