# LaunchDarkly: Major incident: Data attribution issues with Experimentation

**Summary:** LaunchDarkly reported a major Experimentation degradation starting 2026-02-12 23:30 UTC, lasting 4 h 8 min, with certain experiment iterations receiving incorrectly attributed data. The incident was resolved at 2026-02-13 03:39 UTC; LaunchDarkly confirmed results for active experiments were accurate again. _(machine-written, sol)_
- Kind: Major incident · Label: degradation (model (Jev))
- Changed: 2026-02-12 23:30 UTC · Detected: 2026-10-17 18:22 UTC
- [Source: https://stspg.io/rn2jwjqqvff4](https://stspg.io/rn2jwjqqvff4)
- [Company: LaunchDarkly](https://rewindex.com/company/launchdarkly.md)
- Versions: before (none: first archived) → after incident\_version:195/hfbvlcjhn2cr@0b5db704d01b
- Change 1 of 1 for this incident

## What changed

**1. Added: Title**

```diff
+ Data attribution issues with Experimentation
```

**2. Added: Impact**

```diff
+ major
```

**3. Added: Status**

```diff
+ resolved
```

**4. Added: Start time**

```diff
+ 2026-02-12 23:30 UTC
```

**5. Added: Resolved time**

```diff
+ 2026-02-13 03:39 UTC
```

**6. Added: Affected components**

```diff
+ Experimentation (core functionality) - Experiment results analysis, Experiment results analysis
```

**7. Added: Update** (investigating) · 2026-02-13 00:30 UTC

```diff
+ We are investigating an issue where certain experiment iterations are receiving incorrectly attributed data.
```

**8. Added: Update** (identified) · 2026-02-13 01:32 UTC

```diff
+ The team has identified the root cause and is working on a fix.
```

**9. Added: Update** (identified) · 2026-02-13 02:38 UTC

```diff
+ We have fixed the data attribution issues where certain experiment iterations are receiving incorrectly attributed data for any new experiments that are created.  We are fixing the data attribution error for active experiments.
```

**10. Added: Update** (resolved) · 2026-02-13 03:39 UTC

```diff
+ We have fixed the data attribution issues where running experiment iterations were receiving incorrectly attributed data. This incident is now resolved and results for active experiments are now accurate.
```

## History of this incident

| When (UTC) | Change | Label |
| --- | --- | --- |
| 2026-02-12 23:30 UTC | Major incident: Data attribution issues with Experimentation (this change) | degradation |

All LaunchDarkly changes: [timeline](https://rewindex.com/company/launchdarkly/changes.md)
_Diff excerpts are shown on normalized text: dates, counters and tokens appear as ‹date›, ‹count›, ‹tok›; noise-only edits are hidden. Rewindex shows the changed passages, not a copy of the page._


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Canonical: https://rewindex.com/change/i02bf148fea8181 · Markdown: https://rewindex.com/change/i02bf148fea8181.md · JSON: https://rewindex.com/api/v1/changes/i02bf148fea8181 · Generated 2026-10-18T00:38:12.329Z