Short answer: it helps, but it isn't required. Here is what a resale certificate is, why wholesale suppliers ask for one, and what institutional buyers provide instead.
Most wholesale suppliers like to know who they are selling to, and a resale certificate is the usual way to show it. We welcome one — but it is not required to request a quote.
What a resale certificate is
A resale certificate is documentation that you are buying goods to resell rather than as an end user. It is standard in business-to-business supply. If you have one, you can add it to your quote; if you do not, you can still request pricing.
Why a legitimate supplier requires it
Qualifying buyers keeps the channel wholesale — resellers and institutions, not the public. It is also part of keeping the research-use-only framing intact from supplier to reseller.
What institutions provide
Universities, labs, and other institutional buyers can supply organizational documentation in place of a resale certificate. Either way, you share it once, up front, in the quote request.