The first woman to head an Indian unicorn is now the country’s youngest self-made woman millionaire

The first woman to head an Indian unicorn – a startup valued at over $1 billion – has added another impressive title to her name.

Ambiga Subramanian, former CEO of data analytics firm Mu Sigma, is the youngest of India’s eight richest self-made women, according to the Hurun India rich list 2017, published on September 26 by Shanghai research firm Hurun Report.

With a net worth of over Rs 2,500 crore, Subramanian ranked fourth after Kiran Mazumdar-Shaw, chairperson of biotechnology company Biocon, Vembu Radha, director at software products maker Zoho, and Sheela Gautam, chairperson emeritus of mattress-maker Sheela Foam.

The Hurun India rich list ranks Indians with wealth in excess of Rs 1,000 crore.

Last year, 42-year-old Subramanian sold her 24% stake in Illinois-based Mu Sigma to her former husband Dhiraj Rajaram, the company’s founder and chairman, following their divorce. Rajaram then went on to buy stock options held by his employees to finally emerge as the controlling shareholder of the firm he established in 2004. Mu Sigma is estimated to have a valuation of $1.5 billion.

Subramanian and Rajaram first met in the early 1990s at the College of Engineering, Guindy, in Chennai, where they were both studying electrical engineering. The two later went on to study computer engineering at Wayne State University in Michigan.

Subramanian, ranked among India’s most powerful businesswomen by Forbes last year, began her career in 1998 with the American telecom major Motorola, where she worked for eight years. Rajaram worked with consultancies such as Booz Allen Hamilton and PwC before striking out on his own with Mu Sigma, which he funded by selling their home in Illinois and putting in $200,000 of his personal savings. Subramanian joined him in 2007.

As she explained to YourStory in 2013:

“When Dhiraj started Mu Sigma, I did not join him because we had a year-old baby and we didn’t want to keep all our eggs in one basket. So I had a more stable job at that time. But after a few years, Dhiraj had struck a big deal and he and his colleague were talking about it when they suggested that I join them to manage the new client. My first engagement with Mu Sigma was to take care of one of the client engagements out of Chicago.”

According to her LinkedIn profile, Subramanian started off as director for innovation in 2007, going on to become the company’s head of talent management in 2010. In 2012, she took over as the chief operating officer, which she remained till January 2016, after which she became CEO. Subramanian is yet to respond to a questionnaire from Quartz.

Mu Sigma grew rapidly on the back of a model that delivered big-data analytics to multinational corporations from centres in India. Today, it employs over 4,000 workers and serves 140 of the Fortune 500 companies.

In 2012, it crossed the $100 million revenue mark and went on to became India’s first profitable unicorn. For financial year 2015-16, Mu Sigma posted a profit of Rs 462.9 crore (paywall), a 22% increase from the year before. It has raised over $211 million so far in seven rounds of funding, backed by investors such as Sequoia, General Atlantic, and Mastercard. It counts American companies such as Walmart, Microsoft, and Dell among its clients.

However, 2016 didn’t go quite well.

Internal crisis

Last year, the company faced some serious turmoil when Subramanian and Rajaram decided to get divorced, and senior executives began quitting amidst talk of a power struggle between the couple. In March, Goutham Ekollu, the head of operations who had been with the company for a long time, left. He was followed by Sayandeb Banerjee, head of delivery, in August, and several mid-level delivery managers.

The resulting chaos led to loss of business. In the year ended December 2016, Mu Sigma’s revenues fell to $165 million, from $184 million in 2015.

The turmoil was finally put to rest when Rajaram bought out Subramanian’s stake.

“We have built a great company over the last 11 years,” Subramanian said in a statement at the time. “Due to personal circumstances, it is time for me to move on from the management team of the company and do something different. All rumours about me starting a competitive firm are untrue. While there is a lot of interest in the market to invest into a promising and profitable company like Mu Sigma, I have agreed to support Dhiraj’s interest to purchase my shares and get a controlling stake that will allow him to fulfill his vision.”

Since her exit, Subramanian has largely stayed out of public eye. Mu Sigma, meanwhile is back on track and is looking at revenues in excess of $180 million in 2017.

This article first appeared on Quartz