The firm began in Manhattan as Shazi Visram's response to a shortage of organic baby and toddler foods, The Wall Street Journal reported Monday.
The firm was sold over the weekend for hundreds of millions of dollars, Visram said, but she would not be more specific than that on the price, the Journal said.
Visram said she would keep the management team and remain chief executive officer, although the company will have a new board of directors.
The company that began with sales to five local Gourmet Garage and Fresh Direct stores was available in 20,000 stores as of 2012, when revenues quadrupled to $62.5 million from $13.3 million in 2010.
The company now has 120 employees, including 70 "Happy Mamas" who do sales work and interact with local mothers, the Journal said.
"I knew that at one point we would want to bring on a major partner to take the business to the next level," Visram said.
She said Danone's track record on corporate and social responsibility made the two companies a good match.
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