Former Cosatu general secretary Zwelinzima Vavi and EFF leader Julius Malema are plotting to overthr.
The fund invested in the Sanral e-tolling scheme by holding bonds at the agency. The fund holds roughly 50% of Sanral bonds, valued at about R15.7-billion.
Last week the fund board chairman Arthur Moloto dismissed suggestions that the fund had tried to hide its investments in Sanral, saying details of all its investments had been published in their 2010-11 annual report.
He confirmed that as of last month the fund held "roughly 50% of Sanral bonds, valued at about R15.7-billion", but maintained this was a sound investment.
Moloto was responding to IFP finance spokesman Narend Singh, who claimed why the reason the government was adamant about e-tolling was that the state pensions had invested in the scheme.
Despite resistance from the business community and unions, the government has been steadfast about the e-tolling system proceeding. To attest to this, Gauteng premier Nomvula Mokonyane and other MECs led the way by registering their vehicles for e-tolling.
"The fund wishes to state that it has nothing to hide from South African citizens with regard to its holding of the Sanral bonds or any other bond holding for that matter," Moloto said.
"Our investment in conventional and inflation-linked bonds, issued by government and state-owned entities (including Sanral), is informed by our investment policy that takes into account our long-term liabilities as a pension fund.
"We are steadfast in our view that investment in economic infrastructure, including the country's road network, is critical to the growth of the South African economy and infrastructural investments remain an attractive asset class with potential for excellent returns in our overall portfolio."
Cosatu has rejected the e-tolling system and staged a march over a week ago, vowing that the fight against the new system was not over.