Shares in US gaming and casino companies jumped yesterday as investors wagered on new business opportunities for the industry after the US Supreme Court paved the way for states to legalise sports betting. 

Shares in European bookmakers, including Paddy Power Betfair  and GVC Holdings, also moved higher in brisk trading. 

The US ruling endorsed New Jersey's bid to allow sports betting and struck down a 1992 federal law that widely prohibited the practice.

This potentially adds a new line of business for many casinos and for betting technology providers such as Scientific Games and International Game Technology. 

It takes the US a step closer to the possible expansion of legal sports betting nationwide, rather than in select places such as Nevada, home to gambling capital Las Vegas. 

The illegal sports betting market is worth billions of dollars annually. 

Scientific Games is particularly well placed to benefit from the ruling due to its acquisition in January of Canadian digital gaming and sports betting firm NYX Gaming Group, analysts said. 

Scientific Games shares were last up 11.6% at $59.53, a record high, with trading volume 4.6 times the 10-day moving average. 

International Game Technology shares were up 3.4%, on track for their biggest one-day percentage gain since early March. 

Shares in racetrack and casino operator Churchill Downs hit a record high and were last up 5.5% at $294.41 with trading volume 2.9 times the 10-day moving average. 

In London, shares in William Hill, which operates legal sports betting in Nevada and is preparing to start operating in New Jersey, rose 10.7%. 

The company could be ready to take bets in less than a month from New Jersey's Monmouth Park Racetrack if the state gives it the legal go-ahead, William Hill US CEO Joe Asher said. 

"We're going to get ready to open for business as soon as possible," said Asher, who estimated that $10 billion is bet on sports annually in New Jersey. 

Since bookmakers typically keep about 5% of a bet, that would represent a $500m business in that state alone. 

William Hill has infrastructure in place in Delaware as well as New Jersey, but Asher did not give a timeline for starting operations in that state. 

Analyst have estimated that the market for legal sports betting could range between $1.2 billion and $57.6 billion of total wagers, with proceeds for gaming operators between $62 million and $2.9 billion. 

They also said negotiating regulations and issuing licenses could be time-consuming and push earnings out further than some investors might expect.