The poker giant said it had secured the investment from two new investors, led by Barclays Capital and Waddell and Jones Capital.
PokerStars said it was seeking an additional $2 billion in funding, which it plans to use to expand its global operations and accelerate the launch of new products.
Ladbrokes is an Australian online gambling and casino company.
The firm is also part of the world’s biggest online poker company, Bet365, which also has a presence in the US.
Online gambling has exploded in popularity in recent years, as more players use poker machines to play games of chance.
“Ladrokes is pleased to be investing in PokerStars, which will continue to build its customer base globally,” said Simon Pugh, chief executive of Ladbroke, in a statement.
“Ladder-based online poker is one of the fastest-growing segments in online gaming, and the company has a track record of delivering top-notch customer experiences, including a strong online poker player loyalty program, excellent customer service, and world-class technology.”
The online gambling business, which launched in Australia in 2005, has more than 4,400 casinos worldwide, according to Ladbrokers data.
Poker has been growing rapidly in the world of online gaming.
The total online poker market is expected to grow at a rate of 8% in 2019, according, to a recent study by industry consultancy The Pinnacle Group.
The growth in online poker has been fuelled by a growing appetite for riskier online games.
In November, the largest online poker sites – including PokerStars – were valued at $13 billion.