The Gupta family will on Friday morning file responding court papers at the High Court in Pretoria t.
FAK managing director Danie Langner said the song, initially written as a poem by CJ Langenhoven in 1918, remained a precious cultural heritage for many Africans.
"Cultural songs should have a proper place at cultural festivals... nations are built through respect and recognition of both national and cultural symbols."
He said the singing of old folk melodies did not equate to nostalgia for a South Africa before 1900.
His comments followed the singing of "Die Stem" by popular Afrikaans musician Steve Hofmeyr at the weekend.
Hofmeyr sang the song to a 45,000-strong crowd at the Afrikaans cultural festival Innibos in Mbombela.
A video of the event shows the crowd singing along and cheering and whistling when the song is finished.
Hofmeyr subsequently posted the video and his views on the event on his Facebook page.
He said: "I will sing it more and I ask that the ban on our sacred traditional song be lifted and all may be free to sing what they want, where they want, as long as it is not hate speech or preaches violence."
He advised his fans to continue singing the song because it was legal, did not contain hate speech and was written by a South African for the country two decades before apartheid.
In an editorial titled "Are our memories so short?" in the Beeld newspaper on Tuesday, editor Adriaan Basson criticised Hofmeyr's reasoning.
"Steve can say what he wants but the comments on social media speak for themselves. For thousands of people his singing of 'Die Stem' was a reminder of the 'good old days' of apartheid, when the white man was boss and blacks were working class," he said in Afrikaans.
"It is a beautiful poem and Langenhoven was one of our best writers ever... but it would be extremely naive, if not dishonest to the song to try and loosen its political significance."
Basson said the song unfortunately represented a system of white-on-black oppression for most citizens and was as inseparable from apartheid as the Blue Bulls song was from Hofmeyr.
He wondered whether people were again being deceived by a leader, this time with a guitar in hand.
According to FF Plus spokesman Anton Alberts, the Economic Freedom Fighters on Tuesday called on Parliament for the 'Die Stem' portion of the national anthem to be scrapped.
He said EFF MP and national spokesman Mbuyesi Ndlozi made the comment during a joint meeting of the portfolio committees for Communication and Telecommunications and the Postal Service in Parliament on Tuesday.
Ndlozi was not immediately available to confirm whether he had made the comment.
"They have to realise that they are playing with fire by targeting minorities and in particular the Afrikaners and that it is time for them to grow up and practise responsible politics to the advantage of all South Africans," Alberts said.
"This means on a national level that there is room for a conciliatory national anthem which exists at present and at cultural events of different cultural groups in South Africa people may sing that which is dear to their hearts without harming anybody else."
He said citizens should tolerate cultural songs as much as they did freedom songs.
Users on social networking site Twitter had mixed views.
Author and columnist @MaxduPreez commented: "Oor Steve Hofmeyr wil ek net een ding se: Goddank, ons is nie almal so nie" [On Steve Hofmeyr, I just want to say one thing: thank goodness we're not all like that].
News24 editor-in-chief Jannie Momberg (@JannieMom) said he personally would never have included "Die Stem" as part of the new national anthem after 1994.
Erna, known as @HSPieterse, said: "Hoop ons hoor Die Stem as Bonus op jou volgende CD! Flippen nice, hoor!" [Hope we hear Die Stem as a bonus song on your next CD. Flipping nice!].
Another user wanted to know why it was okay to sing the song at a rugby test match with 45,000 people but not at a cultural festival with the same crowd size.
Asked what the African National Congress's view was on the incident, national spokesman Zizi Kodwa said he was not immediately available to comment as he had been in a workshop all day.
He said a statement was likely to be released later on Tuesday.