The London Stock Exchange Group said that it had agreed to buy a majority 60 percent stake in British clearing house LCH.Clearnet for 463 million euros ($613 million), ending months of talks. LSEG, which owns the London and Milan stock exchanges, had been in talks with LCH.Clearnet about a transaction since last September. Clearing houses play a key role in the transaction of shares between two parties, charging clients a fee to guarantee deals should one side default. \"LCH.Clearnet Group Limited and London Stock Exchange Group plc today announce that they have reached agreement on the terms of a recommended cash offer,\" said a statement issued by the groups on Friday. \"On Completion, LSEG will become the majority owner of LCH.Clearnet, holding up to 60 percent. of LCH.Clearnet\'s issued share capital.\"