The report adds: "Three of Savile's victims were only nine years old."
It is understood that the report will be officially published within six weeks.
Some who work at the BBC told the inquiry in interviews that they had heard about Savile's predatory sexual conduct.
However they feared reporting concerns to managers, it is claimed.
The report reads: "I heard of incidents that took place in virtually every one of the BBC premises at which he worked.
"These included the BBC Television Theatre (in connection with Jim'll Fix It), at Television Centre (in particular in connection with Top of the Pops), at Broadcasting House or Egton House (where he worked in connection with BBC Radio 1), Lime Grove studios and various provincial studios, including Leeds, Manchester and Glasgow.