The fraud operations team at a national wireless telecommunications carrier identified a statistically anomalous cluster of SIM-card modification requests — account changes in which a subscriber's phone number was transferred to a new SIM card, typically as a precursor to account takeover at financial institutions that used SMS-based authentication. Internal review suggested that some of the modifications had been processed by carrier employees despite inadequate customer verification — raising the possibility of insider complicity. The carrier's outside litigation counsel engaged Law & Forensics to conduct a forensic investigation under privilege, with the dual objective of mapping the fraud ring and assessing the scope of potential insider involvement before any employee actions or law enforcement disclosures were made.
The Situation
SIM-swap fraud sits at the intersection of telecommunications vulnerability and digital banking security, and it presents an investigative challenge that neither telecom forensics nor financial fraud analysis can address in isolation. The carrier in this case had customer-authentication controls that were technically compliant with FCC account-security regulations but that were being systematically circumvented through a combination of social engineering and insider facilitation. The resulting harm was realized not at the carrier level but downstream — in the victims' online banking, cryptocurrency exchange, and investment accounts, where the fraudsters had used the hijacked phone numbers to reset credentials and drain balances.
Attributing the losses, identifying the network, and documenting insider involvement required the ability to move fluidly between telecom system records, financial institution transaction data, and cryptocurrency ledger analysis.
Our Approach
Law & Forensics organized the investigation across three integrated workstreams, combining telecom-system forensics, digital banking transaction analysis, and insider-threat investigation.
Telecom System Forensics. The team conducted forensic analysis of the carrier's customer account management systems, call center interaction logs, and retail store transaction records, identifying the universe of SIM modifications that bore the hallmarks of fraudulent processing — insufficient verification, unusual request patterns, and anomalous employee-activity signatures. Statistical pattern analysis identified four retail-location employees whose modification activity was statistically inconsistent with peer behavior and consistent with insider facilitation.
Digital Banking and Cryptocurrency Tracing. For each identified fraudulent SIM modification, the team traced the downstream financial harm by working with affected financial institutions (under appropriate legal process) to map account takeover events to the corresponding SIM-swap timeline. Cryptocurrency forensics — applied to addresses and transactions identified through blockchain analysis — traced the liquidation of stolen funds through multiple exchange and mixing-service hops, identifying wallet clusters attributable to the fraud ring's principals.
Insider-Threat Investigation. Law & Forensics conducted a separate forensic investigation of the four identified employees, encompassing their carrier system access logs, personal financial records obtained through legal process, and digital communications. The investigation documented payments — received through peer-to-peer payment applications — from external accounts linked to fraud ring members, establishing the financial nexus between the insider employees and the external network.
Law Enforcement Coordination. The firm prepared a structured evidentiary package — organized for direct use by federal law enforcement — that presented the forensic findings in a format calibrated for grand jury presentation, including timelines, link analysis charts, financial flow diagrams, and source documentation.
The Impact
The forensic investigation produced a complete operational map of the fraud network: 19 individuals, including 4 carrier employees, across a scheme that had operated for 14 months and caused more than $38 million in customer losses. The evidentiary package provided to federal law enforcement supported a grand jury indictment of 11 individuals. Four carrier employees were terminated and referred for prosecution.
A parallel civil recovery action, filed by the carrier and affected customers, has to date recovered more than $9 million. The carrier implemented a redesigned account-authentication protocol — developed with Law & Forensics' input — that has materially reduced SIM-swap fraud rates while remaining compliant with FCC account-security requirements.
Related Practice Area
Digital Banking Services — Account Takeover and Payment Fraud Investigations; Cryptocurrency and Blockchain Tracing; Insider Threat Analysis; Digital Fraud and Financial Crime; Law Enforcement Referral Support
