# FDA Warning Letter: Marcus Research Laboratory, Inc.
> 2021-10-19 · Division of Pharmaceutical Quality Operations III · `e328fa47b66871f9`
## Letter
- **Company:** Marcus Research Laboratory, Inc.
- **Posted Date:** 2021-10-19
- **Letter Issue Date:** 2021-09-30
- **Issuing Office:** Division of Pharmaceutical Quality Operations III
## Subject
CGMP/Active Pharmaceutical Ingredient (API)/Adulterated
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*Source: [FDA Warning Letters](https://www.fda.gov/inspections-compliance-enforcement-and-criminal-investigations/compliance-actions-and-activities/warning-letters) · AI Analytics · CC0 1.0*