Nasdaq network issue hits US equity data feeds

On October 15, 2026, Nasdaq (NDAQ) reported a network disruption at its Carteret, New Jersey data facility that affected data delivery across its US equities markets. A system-status alert issued at 11:27:50 a.m. ET notified market participants of intermittent data gaps. The incident involved network issues within the data centre rather than a scheduled change or planned maintenance. The alert framed the problem as an ongoing technical fault rather than a brief glitch.

The disruption affected multiple multicast groups that distribute market data to trading firms and other subscribers. Both hardware and software-based feeds were hit, indicating the problem cut across different elements of the exchange’s data infrastructure. As a result, the impact extended to various client connectivity configurations, not just a single type of interface.

Nasdaq stated that both the primary “A” feed and the secondary “B” feed originating from the Carteret facility were compromised by the outage. These feeds carry data for Nasdaq’s main equities market as well as its related venues. The disruption affected Nasdaq, Nasdaq Texas and Nasdaq PSX, covering a broad slice of US equity trading activity.

Because both the main and backup Carteret feeds were impacted, some firms experienced intermittent gaps in the data they received. Market commentary noted that these gaps could affect how traders and liquidity providers see order book depth. During the incident, participants relying on the affected streams faced the risk of incomplete or delayed information.

To preserve market access, Nasdaq advised clients to shift their systems to unaffected backup feeds hosted at a Chicago facility. These backup streams were described as not impacted by the Carteret network issue. Firms were encouraged to route their production systems to these alternative feeds to maintain continuity of trading operations.

Nasdaq also told clients that, if they experienced gaps in their data records during the disruption, they should submit recovery requests. This process is intended to allow participants to obtain any missing messages for their records and post-trade processing. The guidance applied across the US equities venues affected by the Carteret-based feeds.

Reporting and market commentary highlighted that even with backup feeds available, intermittent data gaps can influence trading conditions. While systems switched to Chicago-based streams, some participants could see reduced visible depth or less consistent data during the transition. Such conditions may affect execution quality for certain orders while firms adjust their configurations.

Nasdaq said it was actively investigating the network disruption and issued an apology for the impact on clients. The combination of a broad feed interruption, the need to fail over to Chicago, and the subsequent recovery process underscores the dependence of US equity markets on resilient data infrastructure. The incident illustrates how technical issues at a single data centre can have market-wide implications until backup arrangements are fully in place.