A call goes out normally, connects and rings. On the handset it arrives under a warning. Your recipient reads that warning before deciding whether to answer. Your own systems record a normal call, because on your side it was one.
Your provider has finished its part by the time this happens, and has no field to unset afterwards. The company that applies the label sells analytics to the carrier rather than service to you.
Who applies the label?
The carrier that delivers the call to the handset applies the label, usually through an analytics partner.
The FCC, the US communications regulator, makes providers responsible for analytics work they give to another company. In its order in volume 86 of the Federal Register (FR), page 17726, published 6 April 2021, the Commission says it "expects voice service providers to satisfy those requirements, whether or not they use a third party". It also "declines to allow voice service providers to avoid liability solely because they make use of a third-party" analytics service. The provider stays liable for the analytics work even when another company performs it.
This is why the instinct to raise a label with your own provider mostly fails. Your provider originated the call. The label was written by the terminating provider's analytics against a number. There is no field on your side to unset. What your provider controls is what it can assert about you on the way out. That is STIR/SHAKEN, the framework that signs the calling number so the far end can check it. What is STIR/SHAKEN covers how the levels work.
Bird states the same limit on its own side. The caller IDs guide lists what happens to a number after it leaves the platform. Among the things outside a carrier's control it names "Spam and fraud filtering applied by terminating operators" and "Do-not-originate lists and regulator-mandated blocking", alongside anti-spoofing frameworks and origin-based restrictions.
Was my call labeled, or was it blocked?
A blocked call never connects and returns a response code; a labeled call connects and rings with a warning on the handset.
A blocked call does not connect, and it says so. The signal comes back in either SIP or the Integrated Services Digital Network (ISDN) User Part that carries calls on the older network. The FCC requires a terminating provider that blocks a call to "immediately notify the caller that the call has been blocked by sending either a Session Initiation Protocol (SIP) or ISDN User Part (ISUP) response code, as appropriate". It also requires every provider in the path to carry that code back to the origin. So a block arrives at your end as a failed call with a response code attached. What do SIP response codes mean covers reading one. The call log is where the code and the outcome sit together.
A labeled call connects. It rings, and the record shows a normal call. If nobody answers, it reads as an unanswered call rather than a rejected one. There is no code, no rejection reason and no event. The only reliable evidence is a phone in the destination country, which is why labeling is usually discovered by a customer rather than by monitoring.
The two outcomes have different causes. They also carry different amounts of recourse.
What recourse do I have?
A block gives you a defined process. A label gives you no equivalent, because the FCC declined to extend one.
The same FCC order sets out three things a blocking provider owes a caller. It must send immediate notification with a response code. It must disclose a list of blocked calls to subscribers on request. And "when a calling party disputes whether blocking its calls is appropriate", it must "provide a status update to the party that filed the dispute within 24 hours".
The Commission created no corresponding redress process for labeling and instead encouraged providers and analytics partners to work with callers. Under the heading "No Redress Requirements for Labeling", it wrote:
The Commission declines to extend redress mechanisms to erroneous call labeling at this time. Rather, the Commission encourages voice service providers and their analytics partners to work in good faith with callers to avoid erroneous labeling so consumers can better decide whether to answer a call.
A caller disputing a block gets a status update within 24 hours. A caller disputing a label has no equivalent deadline.
Each terminating provider's blocking-dispute contact must also handle callers trying to verify their calls after caller ID authentication information affected them. The Commission "requires that the point of contact which terminating voice service providers have established to handle blocking disputes also handle contacts from callers that are adversely affected by information provided by caller ID authentication seeking to verify the authenticity of their calls". That contact exists at each terminating provider, and it is obliged to take a call about authentication information. It is the closest thing to a defined path when a label follows a number rather than a campaign.
What actually changes the outcome?
Two things are yours to change: what your provider can vouch for, and what your traffic looks like from the outside.
What can be attested. Attestation is what the provider signing a call asserts about your right to the number. It is one of the inputs the standards intend for this exact purpose, described in the FCC's earlier order as information to "enhance the spam identification solutions that terminating voice service providers enable for their customers". The level a provider can assert turns on whether it can confirm both the caller and the caller's right to the number. A number the carrying provider issued therefore sits differently from one you own elsewhere and present through it. Bird's own guidance is to prefer numbers procured through the platform for exactly this reason, and to verify the ones you do not.
What the traffic looks like. Analytics act on a number's behavior over time, and no provider publishes the criteria. There is no threshold to stay under. There is also no setting to change once a number has a reputation.
What you can observe is your own answer rate, per number and over time. A number whose answered calls fall away is the first thing you see from your side, before any customer reports the label. The call log carries that, and what is a call detail record covers reading answer rates without double-counting the legs of a forwarded call.
In short
The label belongs to the receiving carrier, not to yours.
It is applied by the provider terminating the call and its analytics partner. The provider that carried the call has no field to unset.
Blocked and labeled are different outcomes with different evidence.
A blocked call comes back with a SIP or Integrated Services Digital Network (ISDN) User Part response code. A labeled call connects and rings, so your own logs show it as a normal call.
The FCC required redress for blocking and declined it for labeling.
Blocking carries notification, a list on request and a status update within 24 hours. For an erroneous label the Commission asked for good faith instead.
There is one contact point the rules do reach.
The blocking dispute contact also has to handle callers adversely affected by caller ID authentication information, which is the nearest thing to a labeling route.