Nearly 400 organisations moved critical business loads to IBM servers and storage systems in the third quarter of 2010, the company claims.
This is a record quarterly gain from competitors Oracle/Sun and HP since 2005, when IBM began tracking migrations.
IBM set up a migration programme in 2006 to help organisations move to IBM systems. Since then, 4,500 migrations have been through the programme, the company said.
Most of these migrations are from Oracle/Sun and HP, said IBM, including 532 from Oracle/Sun and 481 from HP in the first nine months of 2010.
The figures from IBM show that competition is healthy for the Oracle installed base, said Ronan Miles, chair of the UK Oracle User Group.
But, he said, there are no statistics to show how many customers moved the other way.
"As a user group, we welcome the obvious competition in the higher end market between IBM, HP & Oracle Sun - this means that customers have the ability to move between suppliers to obtain the best benefits from their investments in application solutions," said Miles.
Hardware has a different economic model to software and major refresh is a fact of life while not causing significant disruption to a business that relies on use of software applications, he said.