Barristers representing alleged victims of Mohamed Al Fayed said the group now has more than 70 clients.
Justice for Harrods Survivors said the number of women “feeling safe to come forward” was “increasing on a daily basis”.
Mr Al Fayed, the former Harrods and Fulham FC owner who died last year aged 94, is accused of multiple sexual assaults after a BBC investigation was published last month.
The claims include five accusations of rape and multiple allegations of sexual abuse.
A spokesman for Justice for Harrods Survivors said on Tuesday that it “now retains 71 clients and is processing a further 220 inquiries”.
Last week, the group, consisting of barristers Dean Armstrong KC, Bruce Drummond, Maria Mulla, and Gloria Allred, said it represented “60 survivors as part of our claim, with more to come”.
Justice for Harrods Survivors said on Tuesday it was “welcome” Harrods had “confirmed that it would not be enforcing any rights it allegedly had over the survivors of abuse who had signed NDAs in respect of any previous settlements that had been made”.
In a statement, Justice for Harrods Survivors added: “In this light, we hope that we are correct to assume that Harrods will, similarly, not be raising limitation as a defence, or any similar legal impediments to the bringing of claims by Survivors which might otherwise be time-barred.
“Our confidence is based upon the fact that Harrods has made its own settlement process public, as well as the very significant reality that the vast number of women now feeling safe to come forward (with Harrods directly inviting them to come forward) is increasing on a daily basis.”
In a statement given to The Telegraph, Harrods said: “There are no NDAs attached to settlements made under the current ownership and Harrods would not seek to enforce any NDAs that relate to alleged historical sexual abuse by Fayed that were entered into during the period of his, Fayed’s, ownership.”
Harrods has been approached for comment.
On Thursday, the Metropolitan Police confirmed it was investigating a number of new allegations made against Mr Al Fayed, in addition to prior reports.
The force said it would carry out “full reviews of all existing allegations” of incidents said to have taken place between 1979 and 2013 to ensure there are “no new lines of inquiry based on new information which has emerged”.
The Met said it was contacting lawyers representing alleged victims to “ensure they have the opportunity to speak with us and report any offences”.
