Coca-Cola Co. shareholders sustained damages exceeding $1.3 billion after the international soft drink conglomerate improperly inflated revenues to boost stock prices artificially, a financial expert retained by suing shareholders has concluded.

The report — called “seriously flawed” by a Coke spokesman — surfaced earlier this month in a seven-year-old securities fraud suit against Coca-Cola by Carpenters Health and Welfare Fund, a union pension fund with major Coke stock holdings. The carpenters fund sued Coke in October 2000, claiming that Coke executives — former Chairman and CEO M. Douglas Ivester foremost among them — in the late 1990s had led efforts to mask faltering Coke revenues by pressuring soft drink bottlers to purchase $600 million worth of excess soft drink concentrate.