Skype's owners, led by private equity firm Silver Lake, will make more than three times their investment - a total capital gain of more than $5 billion - on sale of the company to Microsoft Corp, a source familiar with the deal said on Tuesday.
That was made in around 18 months, a short turnaround for private equity which typically invests with a time horizon of three to five years.
The investor group bought a majority stake in Skype from eBay in 2009 for $1.9 billion in cash and a $125 million note. EBay retained about a third of the company.
Microsoft plans to buy Skype for $8.5 billion.
It is one of the largest capital gains made on a private equity investment, the source said.
Improved IPO markets have meant private equity firms have had success exiting investments via the public markets, and have also found more willing buyers for businesses bought during more difficult times.
However, the higher equity markets have pushed up valuations of assets private equity firms have been trying to buy, making clinching new deals difficult.
Silver Lake and investor Andreessen Horowitz declined comment and eBay was not immediately available for comment.
(Reporting by Megan Davies; Additional reporting by Jennifer Saba and Phil Wahba; Editing by Derek Caney and Tim Dobbyn)