* Just Eat raises full-year revenue forecast
* Six-month revenue rose 44 percent
* Shares fall (Adds detail, CEO, analyst comments, updates shares)
By Emma Rumney
LONDON, July 27 (Reuters) - British takeaway ordering website Just Eat said on Thursday it planned to work more with branded UK restaurant chains, knocking its shares despite an upgrade to its full-year revenue forecast.
Founded in 2001, Just Eat has grown rapidly, listing its shares in London in 2014. Its focus so far has been on serving independent restaurants but it is now branching out, investing in partnerships with chains like Burger King and KFC .
"The success of targeting chained restaurants with outsourced delivery is yet to be proven," said analysts at Berenberg, who have a "buy" stance on the shares.
"However, there are both offensive and defensive reasons for Just Eat to at least experiment with it," they said.
Shares in Just Eat, up 43 percent over the last year, fell as much as 5.7 percent on Thursday. They were down 2.9 percent at 690 pence at 0950 GMT, valuing the business at 4.7 billion pounds ($6.17 billion).
Though the firm, which has seen several management changes this year, raised its revenue forecast for 2017 to 500 million pounds to 515 million pounds ($657-$676 million), from 480-495 million pounds previously, it maintained its core earnings forecast at 157-163 million pounds.
"We intend to reinvest this revenue outperformance into additional profitable growth opportunities, including further building on the momentum within the business and increased collaboration with branded UK restaurants," Interim Chief Executive and Chief Financial Officer Paul Harrison said.
He said Just Eat's investment in partnerships was one of the reasons it had raised its revenue outlook, alongside better-than-expected growth in particular from its international business, which now contributes 43 percent of group revenue.
For the six months to June 30 Just Eat's revenue rose 44 percent to 246.6 million pounds as it continued to win share from its largest competitor - the telephone. Orders increased 24 percent to 80.4 million.
"We ... are pleased that 75 percent of total orders are now placed on mobile devices," said Harrison, who will revert to his finance role when Peter Plumb, the former boss of Moneysupermarket.com, takes over as CEO in September.
Core earnings - underlying earnings before interest, tax, depreciation and amortisation - rose 38 percent to 73.6 million pounds.
Britons have been hurt by a rise in inflation, caused in large part by the fall in the value of the pound since last year's vote to leave the European Union, and by a slowdown in wages growth.
Harrison, however, remained upbeat on prospects.
"That weakness that we read about, that we observe in the consumer market, is not apparent in our results, in our business and experience," he told reporters. ($1 = 0.7612 pounds) (Editing by James Davey and Adrian Croft)