A fifth billionaire has been unmasked in the German family behind perfume maker Coty Inc., which debuted on the New York Stock Exchange yesterday.

Andrea Reimann-Ciardelli, 56, sold her stake in Joh. A. Benckiser, the Reimann family’s closely held investment company, in 2003 for almost $1 billion, according to a person familiar with the terms of the deal who asked not to be identified because the transaction was private. She has a fortune valued at $1.2 billion, according to the Bloomberg Billionaires Index.

Reimann-Ciardelli is a U.S. citizen and resides in Hanover, New Hampshire. Her four adopted siblings -- Renate Reimann-Haas, 61, Wolfgang Reimann, 61, Stefan Reimann-Andersen, 49, and Matthias Reimann-Andersen, 48 -- each own 24 percent of JAB, which is led by a trio of outside executives. Their stakes are collectively worth about $19 billion, according to the ranking.

“The Reimanns like to work outside the public eye,” said Andreas von der Gathen, partner at Bonn, Germany-based management consulting firm Simon-Kucher & Partners GmbH, who’s advised Coty. “The more secret, the less trouble.”

Elke Neujahr, a spokeswoman for the Reimanns, declined to comment on the family’s net worth calculations.

Adopted Siblings

Coty, maker of perfumes endorsed by Beyonce and Heidi Klum, raised about $1 billion in an initial public offering yesterday, pricing the shares at the midpoint of the proposed range. The company’s owners, including the Reimann family, sold 57.1 million shares for $17.50 each, according to a statement. The shares closed down less than 1 percent to $17.36 in New York.

The Reimann family has been expanding its interests in consumer goods and has spent $11 billion in the past 12 months acquiring three coffee businesses, including D.E Master Blenders 1753 NV for $9.8 billion. The company withdrew its $10 billion bid for door-to-door cosmetics seller Avon Products Inc. in May 2012.

The four billionaires have been consolidating their control of the company since the 1984 death of their father, Albert Reimann, who had nine adopted children, each of whom inherited 11.1 percent of JAB. In 1996, they bought out four siblings their father had adopted from his sister, Else Dubbers. Seven years later, they financed the purchase of Reimann-Ciardelli’s stake by selling 60 million shares of publicly traded Reckitt Benckiser Group Plc.

Childless Patriarch

The Reimanns still own more than 10 percent of Reckitt Benckiser, the Slough, England-based manufacturer of Durex condoms and Nurofen painkillers. They also own all of Labelux Group GmbH, which operates luxury retail brands Bally and Jimmy Choo, and Coty, which they bought in 1992 for about $440 million from New York-based Pfizer Inc., the world’s largest drugmaker.

The Reimann fortune dates back to 1823, when Johann Adam Benckiser founded his namesake chemical company in Pforzheim, Germany. Five years later, chemist Ludwig Reimann joined Benckiser as co-owner. One of Benckiser’s heirs eventually ceded his stake in the company to the Reimann family after retiring childless.

Ludwig’s great-great-grandson, Albert Reimann, inherited the entire company when his father died in 1952, and added consumer goods such as adhesive cream and dishwasher detergent.

Fashion Brands

In 1981, Reimann hired Peter Harf, a former management consultant at Boston Consulting Group Inc. Reimann’s heirs appointed him chief executive officer seven years later. Harf leads JAB’s management team with Bart Becht, who serves as chairman, and chief financial officer Olivier Goudet. The three managers together own 4 percent of JAB, according to Tom Johnson, a spokesman for JAB at Abernathy MacGregor Group in New York.

JAB sold shares of Benckiser NV, maker of household cleaning products Vanish and Cillit Bang, on the Amsterdam Stock Exchange in 1997. Two years later, the company merged with British consumer-goods manufacturer Reckitt & Colman Ltd. The combined company, Reckitt Benckiser, generated more than $15 billion in revenue in 2012.

Harf created the family’s luxury retail group, Labelux, in 2006. The company bought fashion brands such as Belstaff and Bally, and purchased shoemaker Jimmy Choo Ltd. in 2011 from private-equity firm TowerBrook Capital Partners LP for about 550 million pounds ($916 million).

The Reimanns began investing in the hot-beverage business last year, buying Emeryville, California-based Peet’s Coffee & Tea Inc. for $941 million and Caribou Coffee Co. for $340 million. JAB agreed to buy Amsterdam-based coffee and tea producer D.E Master Blenders 1753 in April. The deal is expected to close later this year.

“It’s very tough to find any information about the family,” said von der Gathen in a phone interview. “It’s sometimes not even completely clear who belongs to the family and who doesn’t.”