DMandPenfold writes "Within the first 20 seconds of the London Stock Exchange's new matching engine going live on Monday, price data vendors began displaying incorrect prices, blank prices and wrong trading volumes, according to Computerworld UK sources. Thomson Reuters, Interactive Data and Netbuilder are among the largest data vendors, providing share prices to traders, that have been displaying pricing problems on some stocks throughout the week. Even the LSE's own data vendor, ProQuote, experienced problems. Concerns are being raised that there could be mistakenly setup connections or incorrect software interfaces at some of the large data vendors. Alternatively, there may be a data caching issue at the LSE that means data going out is not properly synchronised between different systems."