As part of their efforts to protect consumers from spam and malicious content, mobile carriers continuously monitor and filter SMS traffic across all messaging platforms. While carriers do not publish official schedules or thresholds for their filtering, there are typically seasonal fluctuations in blocking activity that affect legitimate business messaging.

Despite strict compliance with industry guidelines, legitimate messages can occasionally be misclassified as spam, also known as false positives. This often occurs when message templates contain phrases, URLs, or sending patterns that are similar to those used in fraudulent campaigns. Yext monitors deliverability trends and escalates confirmed false positives to carrier partners for review. Carriers periodically adjust their filters to restore normal message delivery once the issue is verified.

Carrier-Specific Rules and Seasonal Adjustments

Carriers adjust their filtering practices throughout the year based on messaging volume and emerging threats.

Key patterns to expect:

• Peak seasons trigger stricter filtering. Holidays, tax season, and major sales events often lead to higher fraud attempts, prompting carriers to tighten spam thresholds.
• Filters update frequently. Some carriers revise their blocking rules on a weekly or even daily basis as threat patterns evolve.
• False positives can still occur. Even fully compliant messages may be misclassified as spam if they contain elements similar to known fraudulent campaigns (e.g., certain URLs, phrases, or sending behaviors).

Yext continuously monitors deliverability and works with carrier partners to identify and resolve confirmed false positives. Once verified, carriers typically adjust their filters to restore normal delivery.

How to reduce False Positives

To help ensure your messages reach recipients:

• Limit links, emojis, and urgent-sounding language. These are common triggers in spam campaigns.
• Personalize content whenever possible. Unique messages are less likely to appear as bulk or automated spam.
• Maintain steady, predictable send rates. Avoid sudden spikes in message volume.
• Monitor delivery receipts. Report any unusual declines promptly.

Why Messages May Be Blocked

Carriers evaluate several factors beyond recipient opt-in when determining deliverability, including:

• Message content and keyword patterns

• Frequency and volume of sending

• Adherence to industry and carrier-specific best practices

Because these filters are automated, some legitimate messages may be temporarily affected while carrier systems recalibrate.

How Yext Responds

When message blocking is detected, Yext (including Hearsay) takes the following actions:

• Monitors deliverability trends in real time.
• Investigates and verifies suspected false positives.
• Escalates confirmed cases to carrier partners for review.
• Works with carriers to adjust filters when multiple customers report the same issue.

These efforts help restore deliverability for all affected numbers.

What You Can Do

To minimize the risk of carrier blocking:

• Ensure message content follows industry guidelines.
• Avoid repetitive or high-frequency messaging in short windows.
• Report delivery issues to support@hearsaysystems.com
  for investigation and escalation.

Ultimately, carriers make the final determination on which messages are delivered to their subscribers. Filtering rules and enforcement levels may change without notice. Yext continues to work with carrier partners to minimize false positives and ensure compliance with evolving messaging standards.