Madonna is one of the artists signed to Live Nation
The merger of ticket agent Ticketmaster and concert promoter Live Nation has been cleared by the UK regulator.
The Competition Commission said that the merger would "not result in a substantial lessening of competition in the market" in the UK.
The decision is a reversal of its provisional ruling. It had been concerned the deal would lead to higher prices and lower quality of service.
The US Justice Department is also investigating the proposed merger.
Impact on competition
The UK Competition Commission revised its opinion that the deal could lead to music fans paying more for tickets to see live performances.
The regulator found that it would not be in the new merged company's interest to shut out competition.
The new company "would suffer significant and immediate losses, with very uncertain prospects for long-term gain," the Competition Commission said.
For music gigs to make money, they usually need to sell out. Therefore, the regulator concluded that it would not be in Live Nation's interest to stop ticket sales through channels other than Ticketmaster.
Similarly for Ticketmaster, the regulator believes it would not be in its interest to stop promoting events organised by companies other than Live Nation - because consumers may then go elsewhere.
The Competition Commission had also been concerned that the deal would hinder plans for German rival CTS Eventim, with which Live Nation already has a partnership agreement, to enter the UK market.
The commission concluded that "the extent of Eventim's success in the UK will be determined by its own efforts and abilities, and will not be affected significantly by the merger".
The deal has been approved in Norway and Turkey. The US and Canada have yet to give their rulings.
Produced 22,000 concerts in 2008
Sold 50 million concert tickets in 2008
Put on performances for 1,600 artists in 22 countries
Source: Live Nation
Seatwave, a European ticket exchange operator, said it disagreed with the ruling.
The firm's chief executive, Joe Cohen, said: "We continue to believe this merger will lead to higher ticket prices for fans. We'll wait to see if the US Department of Justice choose to stand up for fans or give them a lump of coal."
Greg Parmley, editor of IQ magazine, which covers the international live music business, told the BBC World Service: "The commission has seemingly just done a complete about-face."
Sold 141 million tickets worth $8.9bn (£5.6bn) in 2008
10,000 clients in 20 markets
Took control of Front Line Management in 2008
He said it was a surprise that "the Competition Commission has completely reversed its original judgement without stipulating any sort of conditions onto the ruling".
Mr Parmley said that he thought the merger made sense because of the state of the music business.
"Live entertainment is doing better than the recorded music industry but we are not immune - we are going through a recession. It is pretty much inevitable that these big companies will have to consolidate."
When they announced the deal in February, Live Nation and Ticketmaster said the merger would improve ticket price options, increase attendance at events and make ticket technology better.
Los Angeles-based Live Nation is the largest producer of live concerts in the world. According to its website, it produces more than 22,000 concerts a year for 1,600 artists in 33 countries. It also manages many of the artists who play in them.
The company has signed artists including Jay-Z and Madonna to deals that include touring, publishing and albums, as well as huge concert promotion deals with the likes of U2 and Shakira.
Ticketmaster is a major entertainment ticketing and entertainment group. It sold 141 million tickets in 2008.
It also owns the entertainment management group Front Line Management.
The managing director of Ticketmaster UK, Chris Edmonds, said the decision was as an important milestone and brought the companies a step closer to "creating a new kind of live entertainment business".
Paul Latham, from Live Nation UK, said: "We have reassured [fans, artists and others] that by combining the resources of these two companies, we will deliver a better live music experience for the entire sector."