It sounds to me like they were sharing emails they got from their attorneys with themselves and others or simply including others on the correspondence to/from their attorneys – either of which might cancel attorney/client privilege that might otherwise exist.
Raniere, Bronfman, and Salzman assert that certain material seized by the government may contain potentially privileged communications. The three defendants provided lists of attorneys and law firms with which they assert they had privileged communications, either in a personal capacity and/or as a representative of Nxivm. The problem is that each of the three defendants claims attorney/client relationships with some of the same attorneys.
The government set up a privilege review team (the “Firewall AUSA”) separate from the prosecutors and agents responsible for the prosecution and investigation to review potentially privileged materials. On October 22, 2018, the Firewall AUSA contacted counsel for Raniere, Bronfman, and Salzman and requested that each defendant describe the claimed attorney/client relationship.
The Firewall AUSA also requested that counsel for Raniere, Bronfman, and Salzman indicate why they think the inclusion of a co-defendant on an email or communication with a particular attorney does not waive attorney/client privilege.
As of the date of filing, Firewall AUSA received what they say are incomplete responses from the defense counsel.
The government requests that the Court set Friday, November 9, 2018—a date defense counsel agreed is feasible—as the deadline for counsel for Raniere, Bronfman, and Salzman to fully respond to the Firewall AUSA.
***
From this same court filing we also learn some additional information:
– Since October 12, 2018, the government has produced over 96,000 pages of discovery. This includes “substantial productions” of the results of searches of electronic accounts [email accounts, texts etc.] belonging to Raniere, Bronfman, and Allison Mack.
– The government made available to all defendants forensic copies of nearly all the devices seized from the residence of Nancy Salzman.
– The government submitted an updated list of electronic data, noting which defendants have received a copy.

If they included others (non-clients) on emails to their attorneys, or if they later forwarded A/C privileged emails to third parties, that would cancel privilege. And IMO they’re stupid enough to have done it.
Is it true Allison herself is not branded?
Waive privilege or waive hello to more damning witnesses for the prosecution!
Release “Pimp Mac’s” collator ……before ShadowState has a breakdown !