NeuroNate said:

Resolution therefore closed the doors unevenly, and the asymmetry follows from the bulks lists.

This is where I part company with the consensus forming above. A research-chemical supplier selling lyophilised powder labelled research use only is not compounding and is not claiming to. It is a different legal universe with no pharmacy oversight, no patient relationship and no content guarantee, and conflating the two in these threads helps nobody.

CarlaRPh_TPA said:

Two pharmacies quoted me last year, one describing itself as 503A and one as 503B, and I assumed 503B just meant bigger until both stopped within…

Vendor communication red flags for compounded supply:

• Won't provide COA before purchase — walk away
• Claims "100% pure" without analytical data — unrealistic
• No physical address or phone number — accountability matters
• Pushes you to buy more than you need — pressure tactics
• Won't answer questions about their compounding process — transparency is key
• Payment only via crypto or wire transfer — legitimate pharmacies accept cards

A legitimate compounding pharmacy operates like a healthcare business, not a gray market dealer.

Dr.RenalNash said:

A research-chemical supplier selling lyophilised powder labelled research use only is not compounding and is not claiming to.

For compounded supply users considering compounded for the first time: here's a step-by-step guide:

1. Get a prescription from your doctor (telehealth counts)
2. Research 503B compounding pharmacies with good community reviews
3. Verify their FDA registration and inspection history
4. Request a COA for your specific compound before ordering
5. Start with a 1-month supply to test
6. Consider sending a sample to Janoshik for independent verification
7. Track your response compared to brand (if you were on it previously)

A narrower follow-up, since the general answer is now clear:

Why a shortage listing created a legal pathway at all, since a shortage is a supply fact rather than a permission?

Closing the loop on my own question.

The bulks-list asymmetry was the piece I had missed entirely. It explains why one of my two pharmacies is still arguing it can supply and the other simply stopped.