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ForumsBuyer BewareIs there a way to verify if a vendor has been FDA warning-lettered? Page 2

Is there a way to verify if a vendor has been FDA warning-lettered?

DadBodDave Mon, Apr 27, 2026 at 7:10 AM 9 replies 604 viewsPage 2 of 2
MikeFit_NJ
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Apr 28, 2026 at 5:14 AM#6
BenResearch_OR said:
The pattern that distinguishes a bad batch from an exit is behaviour rather than product.

I disagree that testing history is decisive. It tells you what a supplier did when they were being watched. Continuity of behaviour under stress — a late shipment, a failed test, a complaint — is more predictive than any run of good results.

28 23LeilaHI, marcus_mpls, DeniseRN_TPA and 25 others
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labquiet_amy
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Apr 28, 2026 at 2:02 PM#7
DadBodDave said:
Eight months with one supplier, then a change in how they communicate that I noticed before I noticed anything about the product.

Vendor reputation tracking for vendor vetting: I maintain a personal spreadsheet with every order I've placed — date, vendor, batch number, Janoshik result, personal efficacy assessment (1-5 scale), and any issues.

After 19 orders across 4 vendors: average purity 98.3%, zero sterility concerns, 2 shipping issues (all resolved). This data gives me confidence in my current source and documentation if issues arise.

I encourage everyone to track their orders systematically. Community data aggregation makes us all safer.

27 22HPLC_Greg, LibrarianMeg, bri_stats and 24 others
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CarlaRPh_TPA
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Apr 28, 2026 at 10:50 PM#8
MikeFit_NJ said:
I disagree that testing history is decisive.

Adding the part of the answer the thread has not reached. There is a difference between no evidence and evidence of no effect, and this subject is one where the two get swapped freely in both directions.

26 21BrianDallas92, labquiet_amy, emily_PDX and 23 others
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mark_tokyo
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Apr 29, 2026 at 7:38 AM#9

One thing that is still open after tyler_CSCS’s answer:

How people are distinguishing a supplier having a bad batch from a supplier on the way out?

25 20HPLC_Greg, LibrarianMeg, bri_stats and 22 others
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DadBodDave
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May 1, 2026 at 1:53 AM#10

OP back with an update, since a thread like this is useless without one.

Went back through my own correspondence with an earlier supplier and the warning signs were all there in the replies, weeks before the quality changed. I was reading the product and not the behaviour.

25 23JakeBK_lifts, DerekSJ_a1c, paige_pharma and 22 others
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