FORTUNE– Coca-Cola Co. KO plans to raise its stake in Keurig Green Mountain Inc. GMCR , increasing its investment in the specialty coffee maker after earlier this year signing an exclusive pact to develop soft drinks and other cold beverages for a new at-home system.

In a filing with the Securities and Exchange Commission, the beverage giant on Tuesday said it would raise its stake to 16% of Keurig’s shares, which would be an increase from the roughly 10% ownership Coca-Cola announced earlier this year. The earlier investment cost Coca-Cola about $1.25 billion.

Coca-Cola will own roughly 26 million of Keurig’s shares after it completes the latest investment, which is due to be completed no later than February 13. With the latest stock purchases, Coca-Cola would become the largest investor in the coffee company.

“These incremental purchases demonstrate our continued belief that Keurig Green Mountain has substantial growth potential,” a Coca-Cola spokesperson said in an e-mail.

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In February, the companies announced a development deal that would result in Coca-Cola’s products being used in Keurig’s at-home beverage systems. Under the terms of the deal, Keurig is Coca-Cola’s exclusive partner to produce and sell the beverage company’s single-serve pod-based beverages, which are expected to be sold in Keurig’s fiscal year 2015.

The single-serve pods are expected to dispense cold beverages, similar to the popular Keurig coffee pods. The company’s cold system is expected to dispense carbonated drinks, juice, sports drinks, and teas. Some analysts have said they believe Keurig’s investment in cold beverages represents an opportunity to boost global household penetration and increase the company’s share of consumer beverage consumption.

Earlier this month, Keurig reported its fiscal second-quarter net sales increased 10% from a year ago, as the company sold more beverage packs and brewers and accessories. The company also raised its outlook for the year and added $1 billion to a share repurchase program.