Late on Friday, Twitter announced that it would no longer license the full stream of half a billion daily messages on its service to third-party resellers. Anyone who wants access to the stream, known as the fire hose, will soon have to license the data from Twitter directly.

On the surface, the announcement affects just the two remaining buyers of Twitter data, DataSift and NTT, and also suggests that Twitter no longer wants to sell its data wholesale, just retail. But it’s also a deeper sign of the company’s intention to compete with — and perhaps cut out — many middlemen that profit from helping marketers make sense of the flood of tweets to run their businesses more intelligently.

In a blog post, Twitter said the decision was a natural outgrowth of its acquisition of Gnip, the leading reseller of Twitter data, about a year ago. “Direct relationships help Twitter develop an understanding of customer needs, get direct feedback for the product road map and work more closely with data customers to enable the best possible solutions for the brands that rely on Twitter data to make better decisions,” wrote Zach Hofer-Shall, head of the company’s ecosystem program.

What he didn’t say is that Twitter also thinks direct relationships will make more money. Last year, the company generated $147 million, or roughly 10 percent of its revenue, from data licensing and other services, and Twitter’s leaders see data as an area that they have only begun to mine.

Chris Moody, the former chief of Gnip and now Twitter’s vice president for data strategy, sketched out the data vision at a November meeting with Wall Street analysts. “In the future, every significant business decision will have Twitter data as an input, because why wouldn’t you?” he said. “Why wouldn’t you add into your business decision-making, ‘What does the world think about this topic at this particular time or at a previous moment of time, maybe last year when we ran this campaign,’ that type of thing?”

As an example, Mr. Moody described how T-Mobile scanned tweets from customers suggesting they were planning to dump the carrier because it didn’t offer the iPhone. T-Mobile later used that data to target those customers and persuade them to stay, cutting its churn by 50 percent.

While Twitter primarily works with dozens of data analysis and software companies, such as Adobe, Spredfast and Salesforce.com, as a data supplier, it also wants to move up the value chain.

It is already packaging its feed with data from other social sources, such as Yahoo’s Tumblr, and wants to expand that further. That’s a service that DataSift, one of the two resellers that were just cut off, also provides. And Twitter is working with business services companies like IBM to train thousands of consultants and conduct case studies of how Twitter data can transform specific industries.

“We see the data licensing business as extremely complementary to the advertising business,” Mr. Moody said in a February interview. Once businesses understand the customer insights they get from tweets, he said, “when I want to advertise something, where would I turn? Twitter.”

This is far different from four years ago, when Twitter struck licensing deals with Gnip and DataSift. Back then, Twitter didn’t see much value in the data and focused more on selling ads. Now analyzing tweets for everything from stock tips to voter preferences has become big business, and Twitter wants a bigger piece of the profits.

Nick Halstead, chief executive of DataSift, said Twitter was making a mistake by forcing customers to directly license its data. DataSift preprocesses data from about 20 different social networks and makes it available to about 1,000 customers in a form that is easier and faster to use than direct licenses would entail.

Mr. Halstead said DataSift’s business would not take a big hit from Twitter’s move since it still has an arrangement with other social networks, including an exclusive deal to present aggregated Facebook data about the interests of that network’s 1.3 billion users. But, he continued, Twitter’s decision will hurt his customers, who are ultimately Twitter’s customers, too.

“If you are one of these social tech firms, you don’t want to have to broker a deal with 20 different social networks,” he said in an interview on Saturday. “It inconveniences and damages a lot of our customers because they have to work with a lesser-quality product.”

The move is another warning to software developers that any company that is your partner today might very well become your competitor tomorrow. Twitter has a history of granting outside companies access to its services — remember all those platforms like Seesmic that used to let you manage your tweets? — only to take that away when it decides to get into the same business. It has also bought its way into businesses it formerly ignored, such as the Periscope video streaming service and MoPub mobile ad platform.

Indeed, in the February interview, Mr. Moody insisted that Twitter wasn’t planning to get into data analytics and go up against Adobe and Salesforce. “We realize that we are not an enterprise software company,” he said. “We’re going to give you the data.”

As Twitter grows, so does its ambition, and today’s partner might very well be in the company’s gun sights tomorrow.