Was MB Associates hit by ransomware?

MB Associates was listed by the thegentlemen ransomware operation (United Kingdom), and stolen data was published on the group's leak site. Darkfield tracks this disclosure with the original leak post, screenshot and group context.

Who is the thegentlemen ransomware group?

thegentlemen is a ransomware operator tracked by Darkfield. See the full operator dossier for its known victims, sectors targeted, IOCs and leak-site infrastructure.

What data was leaked in the MB Associates breach?

thegentlemen published data attributed to MB Associates. Darkfield captured the leak post and a screenshot of the listing.

Ransomware victim disclosure

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JEM Associates

listed as MB Associates · Claimed by Thegentlemen · listed 21 hours ago

Today

Age

since listed · data leaked

Status timeline

ListedAug 30, 2026
Data leakeddate unknown

At a glance

Group: Thegentlemen
Status: Data leaked
Country: United Kingdom
Sector: Professional Services
Listed on leak site: Aug 30, 2026

About the victim

AI dossier — public-source company profile

JEM Associates (formerly MB Associates) is a UK-based social impact consultancy founded in 2005 by Mandy Barnett. The firm helps organisations understand and increase their social impact through impact evaluation, SROI analysis, consultation, research, creative facilitation, training and toolkits. It serves public sector bodies, charities, arts organisations and cultural institutions.

Industry: Social Impact Consultancy
Address: Holmfirth, West Yorkshire, GB
Founded: 2005

Attack summary

Severity: low — Listing announcement with no proof files, no claimed data exfiltration, and no operational impact stated. The post is purely informational about the company's business and history.

The leak post contains no claim of encryption, exfiltration, or operational disruption. It appears to be a listing announcement only, with no indication of what data the threat actor claims to have accessed or what harm is threatened.

low

What the group claims

mbassociates.org zoominfo.com/c/mb-associates/372858181 MB Associates is a UK social impact consultancy founded in 2005 by Mandy Barnett (London Business School MBA, chair of Social Value UK), based in Holmfirth, West Yorkshire; its legal entity is Mandy Barnett Associates Ltd (incorporated 7 Sep 2005, registered in Welwyn Garden City). It helps people, projects and organisations understand and increase their social impact — impact evaluation, SROI analysis, consultation and research, creative facilitation, training and toolkits — working through a Plan–Do–Review cycle that starts with a "Story of Change". Clients include Arts Council England, the National Lottery, UKRI-AHRC, Natural Resources Wales, Bristol City Council, the National Children's Orchestra, museums and charities; it also runs its own learning platform, Culture3 (culturecubed.org). In February 2026 the founder handed the firm over to colleagues — directors Jael Williams and Emily Wilson — and the brand

Sources

Victim sitembassociates.org

Source

Indexed 21 hours ago

This page surfaces a public ransomware disclosure indexed by Darkfield. Original posts come from the operator's own leak site; we cross-check against ransomware.live, RansomLook and RansomWatch where applicable. Share this URL freely.

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Disclosure context

About thegentlemen

thegentlemen is a ransomware group that emerged in September 2025, operating with apparent financial motivations based on their broad targeting of commercial sectors. The group has documented 267 victims across multiple countries, with primary focus on the United States, Thailand, France, Brazil, and India. Their targeting strategy demonstrates a preference for high-value sectors including manufacturing, technology, healthcare, and financial services organizations. Given the group's recent emergence and limited public documentation from established threat intelligence sources such as CISA, FBI, or major security research firms, specific details regarding their country of origin, operational structure, attack methodologies, encryption techniques, and whether they employ ransomware-as-a-service models remain unclear. The relatively high victim count of 267 in a short operational timeframe since September 2025 suggests either an aggressive campaign pace or potential inflation of victim numbers through affiliate operations, though without corroborating intelligence reports, the group's exact operational capabilities and notable campaigns cannot be definitively established. Current intelligence indicates the group remains active as of late 2025, though comprehensive threat profiling requires additional validated reporting from authoritative cybersecurity sources. The group has been linked to 807 public disclosures across our corpus. First observed on a leak site on September 9, 2025; most recent post August 30, 2026. The operation is currently active.

Also tracked as: the gentlemen.

Timeline of this disclosure

August 30, 2026MB Associates listed by thegentlemenon the group's public leak site

Other recent disclosures by thegentlemen

thegentlemen has been linked to 807 public victims on Darkfield. A sample of the most recent:

See the full thegentlemen dossier →

Sector and geography

This disclosure adds to ransomware activity in the Professional Services sector, which has 17 disclosures indexed across all operators we track. Geographically, MB Associates is reported in United Kingdom, a country with 377 ransomware disclosures in our corpus.

If your organisation is affected

A listing by thegentlemen means MB Associates appeared on a ransomware extortion site and data attributed to it has been published. If this is your organisation, or a supplier you depend on, the priority is to confirm the intrusion and contain it before the window to act closes.

Engage your incident-response team and preserve forensic evidence before remediating — do not wipe affected systems first.
Force a password reset and revoke active sessions for exposed accounts; rotate any credentials, API keys or certificates that may have been in the stolen data.
Assess regulatory notification duties (GDPR, NIS2, sector regulators) — many carry a 72-hour reporting clock from awareness.
Report the incident to your national CERT, NCSC (United Kingdom), as required for your jurisdiction.
Monitor for the data appearing on thegentlemen's leak site and across paste and breach channels, and brief downstream partners who may be exposed through you.

How we know this. Darkfield monitors public ransomware leak sites continuously, archiving every new disclosure and the data later released against the victim. Each entry on this page is sourced from the operator's own publication and cross-checked against complementary OSINT feeds (RansomLook, ransomware.live, RansomWatch). We do not collect or host stolen data — only the metadata, timestamps and screenshots needed to make the public disclosure searchable and accountable. Records here are corrected when the original post is edited, retracted, or merged with another disclosure.