Reasons Bid Requests are Dropped by Beeswax
Before any auctions from exchanges are forwarded to an individual customer's Bidder-as-a-Service, Beeswax performs some basic hygiene on the requests. This document explains some reasons why a bid request would be dropped prior to customer filtering.
The Children’s Online Privacy Protection Act (or COPPA) was created in order to place restrictions on the “operators of commercial websites and online services (including mobile apps) directed to children under 13 that collect, use, or disclose personal information from children.” 
If a bid request is marked as COPPA by the exchange, it means that the request has been identified as:
In order to ensure full compliance with this regulation, all bid requests flagged as COPPA are dropped by Beeswax.
 OpenRTB Spec
If the user ID on a particular bid request is flagged as “opted out”, the bid request will be dropped.
Limit Ad Tracking
“Limit Ad Tracking” (LMT) is a device-level opt-out setting, that allows users to limit the amount of information sent from their device to ad exchanges (including omitting their device ID).
Bid requests flagged as LMT are eligible to bid on if they originate from iOS or tvOS operating systems. We drop all other bid requests flagged as LMT from other operating systems.
Situations Where Bid Requests Are Not Dropped
Do Not Track
We do not honor the “Do Not Track” (DNT) setting. Requests marked as DNT are not dropped or altered in any way.