(Boston, MA)  --  The recent hacking of EBay appears to be the second-largest data breach in U.S. history. 

The company announced yesterday that hackers got access to its entire database of 145 million user records.  EBay says the hackers accessed the database using login credentials obtained from "a small  number" of employees.  The breach occurred between late February and early March and security experts want to know why it took EBay until May to discover it.  Connecticut, Florida and Illinois are conducting a joint investigation into the breach. 

Computer experts say the largest data breach was last October at software maker Adobe Systems. That time hackers accessed about 152 million user accounts.