Mark Delaney, the chief investment officer of $341 billion superannuation giant AustralianSuper, says he is still smarting over $1.1 billion of capital lost on a soured investment in education software start-up Pluralsight.

The super fund giant took a stake in Pluralsight alongside long-standing specialist venture fund Vista, but they were forced to write off billions of dollars earlier this year when the company, which was acquired for $US3.5 billion in 2021, could not pay its lenders.