Factbox: Main findings of Britain's energy market review

LONDON (Reuters) - Britain ordered a full anti-trust investigation into its energy market on Thursday after regulators detected signs of tacit price coordination, kicking off a process that could lead to some of the biggest suppliers being broken up. The country's big six energy companies - SSE, Scottish Power, Centrica, RWE npower, E.ON and EDF Energy - control around 95 percent of the retail market. Prime Minister David Cameron ordered a review of competition last October following public outrage over high energy bills. Below is a summary of the main findings, which indicate the market is not competitive enough. POSSIBLE TACIT COORDINATION Regulators found signs of tacit coordination through the timing and size of price changes and the fact suppliers pass on price rises more quickly than price cuts. The review found no evidence of explicit price-fixing, but said signs indicated competition was being hampered. INCUMBENCY ADVANTAGES The big six suppliers all have a high proportion of customers who never, or rarely switch tariffs. The companies are able to charge these customers higher prices. PROFITABILITY Between 2009 and 2012, retail profits within the sector rose from 233 million pounds ($385.95 million) to 1.1 billion pounds and overall profits for the big six went from 3 billion pounds to 3.7 billion pounds. The regulators also said they question whether a 5 percent profit margin, which the big six defend, is fair. NEW ENTRANTS The vertical integration of the big six suppliers, meaning they all own production as well as supply businesses, makes it difficult for new entrants who do not own such assets to compete against them. The share of independent energy suppliers has now grown to 5 percent, but barriers remain that prevent their expansion. WEAK CUSTOMER RESPONSE The review showed that 43 percent of consumers did not trust their energy suppliers to be open and transparent, an increase from 29 percent in 2012. Despite the discontent, the rate of users switching supplier remains low. ($1 = 0.6037 British Pounds) (Reporting by Karolin Schaps; Editing by Erica Billingham)