Super funds worth $1.6 trillion will begin voting off male company directors from top 200 company boards as they come up for re-election, where they have failed to make any in-roads on gender diversity.

The Australian Council of Superannuation Investors, which holds its annual conference on Tuesday, wrote to the top 200 companies last year putting them on notice it would set a target that boards have 30 per cent of female directors by next year.

While some boards have boosted the number of female directors, only a quarter have reached the 30 per cent target while 20 of the top 200 companies still have no woman on their boards, including top 100 companies Qube Logistics and TPG Telecom. Shareholders vote on the re-election of board directors every three years and while they are normally re-elected with over 90 per cent support, the powerful coalition of super groups including AustralianSuper, Cbus, HOSTPLUS and UniSuper is expected to shake up the director boys' club.

Louise Davidson was shocked to realise that 100 companies in the ASX200 had either fewer than one woman on their boards. Jesse Marlow

Half the index on notice

"Last year, I wrote to all ASX200 companies that had either one or zero women on their boards, that was 100 companies, so half the index. I was absolutely shocked to discover I had to sign 100 letters," ACSI chief executive Louise Davidson told Boss Magazine in an interview to be published on Friday.