Satellite TV and Internet provider Dish has asked the Federal Communications Commission to block Comcast's proposed acquisition of Time Warner Cable (TWC), and it's not a fan of the AT&T/DirecTV merger either.

"The pending Comcast/Time Warner Cable merger presents serious competitive concerns for the broadband and video marketplaces and therefore should be denied. There do not appear to be any conditions that would remedy the harms that would result from the merger," Dish Deputy General Counsel Jeffrey Blum wrote in a filing with the FCC today.

Dish didn't ask the FCC to block AT&T's proposed purchase of satellite provider DirecTV, but the company said it "presents competitive concerns... Among other things, AT&T and DIRECTV will also be able to combine their market power to leverage programming content, to the potential detriment of consumers." AT&T hasn't responded to a request for comment, but it argued previously that it needs to buy DirecTV because its own TV service is unsuccessful, and it claims consumers will benefit from expanded broadband deployments.

As for Comcast/TWC, Dish argued that the combined company "will have at least three ‘choke points’ in the broadband pipe where it can harm competing video services: the last mile ‘public Internet’ channel to the consumer; the interconnection point; and any managed or specialized service channels, which can act as high speed lanes and squeeze the capacity of the public Internet portion of the pipe. Each choke point provides the ability for the combined company to foreclose the online video offerings of its competitors."

A bigger Comcast will also get lower prices from programmers, who would then be forced to "extract even higher rates from smaller pay-TV providers like Dish," Blum claimed. Finally, "a combined Comcast/TWC will have the incentive and ability to restrict programmers’ ability to grant digital rights to competing pay-TV and OTT [over-the-top] video providers," he wrote.

In response, Comcast contends that Dish is simply afraid of facing a stronger competitor. "As our filings have shown, every market we operate in is highly competitive," a Comcast statement to Ars said. "Dish has long been one of our most vigorous competitors, and unlike us has a national footprint available in tens of millions of more homes than a combined Comcast-Time Warner Cable. Dish not wanting stronger competitors isn’t surprising and it isn’t new. Any issues regarding NBCUniversal programming and other video services, whether they be traditional or over the top are already amply covered by pre-existing FCC rules and deal conditions.”

Dish also objected to the Comcast/NBC merger in 2010, saying it "poses grave threats" to the online video market and "the competitiveness of the multi-channel video distribution market." That merger was approved in 2011, with conditions. One condition set by the Department of Justice prevents Comcast from discriminating against traffic from third-party services, but this requirement is set to expire in 2018.

Comcast has argued that its $45.2 billion purchase of TWC won't harm consumers because the companies don't compete against each other in any individual market. Comcast has also promised to divest itself of a few million subscribers.

After the merger and divestitures, Comcast says it would have 29.1 million residential video customers, 27.9 million residential Internet customers, and 13.4 million residential voice customers. It would also have 900,000 commercial video customers, 1.7 million commercial Internet customers, and 1 million commercial voice customers.

The merger would give the company another five regional sports networks in addition to the 11 it already owns.

Sen. Richard Blumenthal (D-CT) argued in a hearing on the merger that Comcast's increased ownership of television content will provide "both the means and incentive to overcharge [its] rivals."

It's not clear how the US government will handle the acquisition yet, but the FCC's review team does include people who objected to previous big mergers.