In Glover Park Group's ninth-floor offices on F Street in Washington, the Stop Mega Comcast Coalition met weekly on Thursday afternoons. It was there, in the lobbying firm's conference room, that the 29-member coalition plotted against Philadelphia-based Comcast Corp.'s $45 billion acquisition of Time Warner Cable Inc.

Over the last year, the coalition was one of many opponents of the proposed deal. In recent months, it trained harsh rhetoric and a sharp focus on getting the government to reject the merger of the nation's largest cable company with the second largest.

And the loudest of the arguments the coalition made - that the merger would concentrate broadband market share in a single company - is the one that ultimately brought the deal down.

Before the stock market opened Friday morning, Comcast abandoned its plan to acquire Time Warner Cable because the government saw the anticompetition issues in much the same way the Stop Mega Comcast Coalition did. Attorney General Eric H. Holder Jr. and Federal Communications Commision Chair Tom Wheeler said in statements Friday that the deal would not be good for consumers and that their biggest concern was, indeed, broadband concentration.

Allowing the transaction to go forward "would make Comcast an unavoidable gatekeeper for Internet-based services that rely on a broadband connection to reach consumers," the Justice Department said in a statement. The Wall Street Journal reported Friday that Holder had authorized a lawsuit to block the deal.

Had the merger gone through, Wheeler said, it would have created a company with the most broadband and video subscribers in the nation.

"Today, an online video market is emerging that offers new business models and greater consumer choice," Wheeler said Friday. "The proposed merger would have posed an unacceptable risk to competition and innovation, including to the ability of online video providers to reach and serve consumers."

Allen Grunes, a former Justice Department attorney who represented some Comcast/Time Warner Cable opponents in the merger review, said the government came around to the view of the merger's foes - the coalition and others.

"For better or for worse, it often takes a village to stop a merger," Grunes said. "You have to have people willing to take it to the government and to complain to the government, and you have to be willing to be into it for the long haul and you have to spend resources."

Almost from the day the deal was announced, Feb. 13, 2014, concentration of broadband assets and what that would mean for the future of the nation's telecommunications emerged as merger opponents' most consistent point of concern.

Early on, Netflix complained that Comcast seemed to be degrading its streaming service.

Though it reached an interconnection deal with Comcast that solved the streaming problems, Netflix filed a petition with the FCC in August 2014 asking it to deny the merger, saying Comcast had used its control over the Internet "to allow its own customers' access to Netflix content to degrade" until Netflix paid a fee.

In September, FCC chair Wheeler redefined the high-speed broadband market as services offered at 25 megabits per second. Based on that definition, Comcast/Time Warner Cable was expected to control more than 50 percent of the national broadband market.

In December, disparate voices individually raising objections to the deal - small content companies, trade associations, public-interest groups, and Dish Network - came together in the Stop Mega Comcast Coalition to lobby more aggressively and cohesively against the deal. (Netflix is not a coalition member.)

Comcast, the coalition believed, was lulling regulators into a discussion of the TV market, which the group saw as less important than the Internet.

"The coalition was determined to shift the conversation away from [TV] video, which it knew would not be particularly interesting to regulators, and to a conversation about broadband," Gregg Rothschild, managing director at Glover Park Group, said Friday.

Dish Network stabbed at the proposed transaction with its list of "53 Ways Comcast Could Sabotage Competition."

Two of them:

Comcast could block cheaper alternatives to expensive big-bundled cable TV, such as online streamers, from reaching customers.

It could demand fees from streamers such as Dish's Sling TV and HBO Now to access Comcast's network. Currently, some online streamers pay an interconnection fee, some don't.

Dish had these fears, and others, even though the FCC approved Net neutrality rules in late February that protected online content companies from Internet companies like Comcast and Time Warner Cable so degrading their entertainment streams that it would give cable TV the competitive advantage.

At times in the months since the coalition launched its offensive, the two factions had seemed engaged in hand-to-hand combat - one side filing a document, the other rebutting with a blog post or e-mailed statement, and vice versa.

On Wednesday, FCC staff informed Comcast that it was favoring sending a decision on Time Warner Cable to an administrative law judge - an action that one former FCC commissioer, Robert McDowell, characterized as the equivalent of firing a "fatal bullet" into the deal.

By Thursday, signs were that Comcast would abandon the deal. On Friday, it did.

For Comcast, the move represented not only a $200 million-plus setback, but a drain of employees' time and corporate energy.

It also dashed Comcast's hopes for inroads into the largest cable markets in the country, New York, and Los Angeles - both Time Warner Cable territory.

"Today, we move on," Comcast CEO Brian Roberts said Friday morning. "Of course, we would have liked to bring our great products to new cities, but we structured this deal so that if the government didn't agree, we could walk away."

He said Comcast was a "unique company with strong momentum. Throughout this entire process, our employees have kept their eye on the ball, and we have had fantastic operating results. I want to thank them and the employees of Time Warner Cable for their tireless efforts."

Said Grunes, the former Justice Department attorney on the side of the merger opponents: "Comcast had tremendously able people working on this. And it was a difficult merger to bring [to success]. It was not an easy call."

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