The ANC has received complaints of vote-rigging and inflated voter numbers in three provinces that supported ANC deputy president, Jacob Zuma for the party presidency.
It is believed that the electoral commission appointed to oversee the nomination and election process in the ANC leadership race is expected to investigate allegations made by some members in KwaZulu-Natal, Northern Cape and Gauteng.
Among the allegations were that the number of delegates to provincial nomination conferences were inflated at the three provinces.
The irregularities included allowing members from unqualifying branches to vote.
The branches were disqualified after they could not make the necessary quorums that enabled them to proceed with branch general meetings.
Only branches in good standing and those that held the BGMs are allowed to send voting delegates to provincial general councils and the upcoming national conference in Limpopo.
When approached for comment ANC spokesman Tiyani Rikhotso declined, saying all nomination issues are being handled by the commission.
Earlier, the ANC-appointed Electoral Commission had expressed satisfaction with the nomination process, declaring it democratic and inclusive.
Commission chairman, Bertha Gxowa also announced that the commission will be ready to release the final list of candidates for the ANC national executive committee next week.
The ANC-appointed commission said it would approach all the nominees to ask each of them if they were available for election, so that the nominee's name could be placed on the ballot paper.
Gxowa said the process was completed without any serious complaints or disputes.
"We are satisfied that the process was democratic and inclusive," said Gxowa.