As Google celebrates its fifth anniversary as a listed company, the FT’s Lex column considers the search giant’s most costly acquisition — YouTube.

Bought in 2006 for $1.65bn in stock, the video streaming site has rocketed to a dominant position in online video . . . But Google shareholders are paying to provide the world with laughing baby clips. Estimates for the cost of streaming over 5bn videos a month range from $400m to $700m annually. While Google does not break out the figures, losses are likely to be in the hundreds of millions. Read more