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longformer-base-4096

Checked against the listed Hugging Face source repository on 2026-10-03. Unknown values are left explicit rather than inferred.

Source repository ↗Compare this model →History & diff →Machine-readable JSON ↗Field-verified 2026-10-03
Evidence statusSource-first verified
Repository revision checked2026-10-03
Full field verification2026-10-02
Source policy →Methodology →

MODEL INTELLIGENCE · SOURCE-FIRST

What is longformer-base-4096?

OMW evidence review3 Oct 2026

Open Model Weights records longformer-base-4096 as a Pending verification-parameter open-weight model in the longformer-base-4096 family, with AllenAI listed as the developer. The checked source repository provides 2 recognized weight artifacts, format evidence for PyTorch and a verified context window of 4,098 tokens. Values that are not evidenced in the checked sources remain explicitly undisclosed or unknown.

The repository declares Apache-2.0. Commercial use allowed under Apache-2.0 conditions. Open Model Weights reports the checked license evidence and classification; this is not legal advice.

No base model is declared in the checked standard lineage metadata, so Open Model Weights does not infer one. A training recipe and standard training-data disclosure were not found by the current verifier.

Source repository ↗Model card ↗Configuration ↗

DEPLOYMENT PROFILE

Weight memory, without pretending it is a deployment guarantee.

These bars visualize weight-only decimal-GB estimates. They exclude KV cache, activations, runtime overhead, optimizer state and sharding.

WEIGHT-ONLY MEMORY

No weight-only memory estimate is available from the verified parameter count.

FIELD EVIDENCE MAP
WeightsVerified
LicenseVerified
Commercial useClassified
ContextVerified
FormatsVerified
LineageNot declared
Training recipeNot disclosed in checked repository
Training dataNot disclosed in checked standard metadata/model card
RuntimeSource-derived · not runtime-tested

LICENSE & USE

Apache-2.0

Commercial use allowed under Apache-2.0 conditions

Declared licenseApache-2.0
ClassificationAllowed
VerificationMetadata only

This section summarizes the checked repository evidence. It is not legal advice.

LINEAGE & PROVENANCE

What the checked sources disclose — and what they do not.

Open Model Weights does not infer a hidden base model or training corpus when the checked sources do not declare one.

LINEAGE
BASE / PARENTBase model not declaredUnknown
not inferred
CURRENT RECORDlongformer-base-4096longformer-base-4096
TRAINING DISCLOSURE
Training recipeNot disclosed in checked repository
Training dataNot disclosed in checked standard metadata/model card
Familylongformer-base-4096

RUNTIME SIGNALS

Compatibility claims stay attached to their evidence level.

Declared and model-card-mentioned runtimes are discovery signals. They are not treated as Open Model Weights runtime tests unless explicitly measured.

DeclaredTransformers
OMW runtime testNot performed

EVIDENCE TRAIL

Sources and observed history.

This is where the article remains auditable: source links on one side, the registry's observed change history on the other.

PrimaryModel Repositoryhttps://huggingface.co/allenai/longformer-base-4096Inspect source ↗PrimaryModel Apihttps://huggingface.co/api/models/allenai/longformer-base-4096Inspect source ↗PrimaryModel Cardhttps://huggingface.co/allenai/longformer-base-4096/blob/main/README.mdInspect source ↗PrimaryConfighttps://huggingface.co/allenai/longformer-base-4096/blob/main/config.jsonInspect source ↗
Repository revision check

Listed Hugging Face source repository SHA unchanged; prior field evidence retained.

Repository revision check

Listed Hugging Face source repository SHA unchanged; prior field evidence retained.

Field-by-field verification

Checked Hugging Face API metadata, exact repository file list, model card and config when accessible.

Registry record created

Previous verification level: discovered-pending.

RELATED RECORDS

Continue through structurally related records.

Family matches are preferred; otherwise the fallback requires the same developer, model modality and declared pipeline task. No quality score or recommendation rank is used.

No close related record is exposed by the current family, developer and task fields.

FIELD-BY-FIELD RECORD

Inspect the underlying evidence.

The editorial layer above summarizes only what the verified registry can support. The sections below expose the exact fields, artifacts, source links and verification states.

WeightsLicenseHardwareFormatsLineageTrainingRuntimeSourcesVerification

01 · WEIGHTS

Exact repository artifacts

Statusverified-available
Accesspublic
Repositoryallenai/longformer-base-4096
Recognized weight files2
Show all 2 exact weight files
HF API file listing ↗

02 · LICENSE

License & commercial use

Declared licenseApache-2.0
License IDapache-2.0
Commercial useCommercial use allowed under Apache-2.0 conditions
Repository license filesNone observed

Classification describes the checked license terms; it is not legal advice.

License / model-card evidence ↗

03 · HARDWARE

Weight-memory estimate

BF16 / FP16Not calculated
FP8 / INT8Not calculated
INT4Not calculated

Total parameter count unavailable.

04 · FORMATS

Formats & precision evidence

PyTorch
BF16: not observedFP16: not observedFP8: not observedINT8: not observedINT4: not observedGGUF: not observed

“Not observed” means no matching repository artifact/name/dtype signal was found; it does not prove no third-party conversion exists.

05 · LINEAGE

Base model & family

Familylongformer-base-4096
Variantlongformer-base-4096
Declared base modelNot declared in model-card metadata
RelationNot declared

06 · TRAINING ASSETS

Recipe & data disclosure

Training recipenot-disclosed-in-checked-repository
Data disclosurenot-disclosed-in-standard-metadata-or-obvious-model-card-section
EvaluationsNot classified by automated verifier
Intermediate checkpointsNot classified by automated verifier

07 · RUNTIME SUPPORT

Declared and mentioned runtimes

Declared libraryTransformers
Declared/taggedTransformers
Mentioned in model cardNone observed
Artifact signalsNone
Tested by Open Model WeightsNo — source-derived support only

Open Model Weights does not claim runtime compatibility unless it is declared, tagged, mentioned by the publisher, or evidenced by an artifact. No inference benchmark is implied.

08 · SOURCES

Field evidence

Primary / declared sources4
Repository revision301e6a42cb0d
Source policyHow evidence is classified →
model_repositoryhttps://huggingface.co/allenai/longformer-base-4096
model_apihttps://huggingface.co/api/models/allenai/longformer-base-4096
model_cardhttps://huggingface.co/allenai/longformer-base-4096/blob/main/README.md
confighttps://huggingface.co/allenai/longformer-base-4096/blob/main/config.json

09 · VERIFICATION HISTORY

Checked, not assumed

Repository revision check

listed Hugging Face source repository SHA unchanged; prior field evidence retained.

Repository revision check

listed Hugging Face source repository SHA unchanged; prior field evidence retained.

Field-by-field verification

Checked Hugging Face API metadata, exact repository file list, model card and config when accessible.

Registry record created

Previous verification level: discovered-pending.

licenseverified
commercial useclassified
contextverified
weight filesverified
formatsverified
base modelnot-declared
training recipenot-disclosed-in-checked-repository
data disclosurenot-disclosed-in-standard-metadata-or-obvious-model-card-section
runtime supportsource-derived-not-runtime-tested