Updated plans for the site include greater integration between the Olympic Village with the Stratford City Development.
The main broadcast centre will be moved to inside the security zone and Fish Island, originally earmarked for car parking, will be released.
As a result, businesses needing to be released will be cut from 301 to 206.
The adjustments should also mean that the 307 objections to the Olympic plans - to be heard at a public inquiry - will be reduced by 80.
Manny Lewis, chief executive of the London Development Agency (LDA), tasked with securing and preparing the land for the Olympic Park, said: "These improvements will help deliver an enhanced legacy for London and Londoners, which has always been the core of our vision.
"The changes also mean that nearly a third of the businesses - and 1,200 jobs - which we originally needed to relocate can now remain where they are.
"This will significantly reduce the impact on local businesses."
Andy Latham owns one of the businesses that has now been "saved" - but he insists this is not good news.
"I won't be able to carry on my business, because the freeholder of the unit I lease will almost certainly sell it to build luxury flats," Latham, who manufactures scenery for theatre and television, told BBC Sport.
"When I was within the proposed zone of the Olympic Park I would have received compensation.
"Now I will get nothing and I won't be able to afford to set up somewhere else."
A spokesperson for the LDA countered: "A lot of businesses told us they didn't want to move.
"This decision will safeguard those businesses and save 1,200 local jobs."
