What causes high unknown rates when validating purchased email lists and are they effective?

Email marketer from Email Marketing Forum shares that high 'unknown' rates in purchased lists often indicate outdated or scrubbed data, as the provider doesn't want to guarantee deliverability on a low-quality list. They suggest verifying a small sample before purchasing a large list.

Email marketer from HubSpot explains that purchased lists are often filled with inactive or invalid email addresses, resulting in low open rates and click-through rates. Purchased lists can be seen as spam and can damage your brand's reputation. They also violate the terms of service of many ESPs, leading to account suspension.

Email marketer from ActiveCampaign explains that sending emails to purchased lists without explicit consent violates anti-spam laws and damages deliverability. Low engagement rates are expected since recipients have not opted in, impacting sender reputation.

Email marketer from Email Geeks shares that purchased lists are time-consuming, annoy recipients, and harm the brand, also Email isn’t a good tool for prospecting.

Email marketer from Reddit shares that purchased lists are legally problematic and have a low ROI due to lack of engagement. Building a genuine list through opt-in methods is far more effective.

Email marketer from Email Geeks points out varying ESP policies on purchased lists, some explicit (Pardot, SFMC) while others (Oracle) focus on legality. Feels ESPs could do more to crack down on the use of purchased lists.

Email marketer from Email Geeks shares that ESPs aren't monoliths but groups with conflicting incentives (deliverability, sales, marketing). Some focus on cash flow, others on Customer Lifetime Value.

Email marketer from Mailjet explains that purchased lists often contain outdated or inaccurate information, leading to high bounce rates and low engagement. They also damage sender reputation, potentially leading to blacklisting and reduced deliverability for legitimate email campaigns.

Email marketer from Reddit explains that buying lists is a waste of money and can lead to serious problems with your ESP. They recommend focusing on building a list organically.

Email marketer from Email Geeks mentions Spam hurts an ESPs' bottom line and domains, and good senders leave, bad senders are good for cash flow but bad for Customer Lifetime Value.

Expert from Email Geeks explains what "unknown" means in email validation, meaning a validator can't determine the validity of the email address. Suggests firing the customer using purchased lists.

Expert from Word to the Wise explains that purchased lists are not effective, because people on the list never asked to be there and will not respond well to emails. Purchased lists are often older and addresses can be full of spam traps.

Expert from Spamresource shares the point that purchasing lists is a 'lazy' practice that is not very effective. The main issue is lack of permission from users. Building a legitimate list is far more effective.

Expert from Email Geeks shares a link to Word to the Wise, stating most successful ESPs ban purchased lists, discouraging the practice and using it as a cause for AUP action when discovered.

Expert from Email Geeks indicates from a previous discussion MailChimp and Marketing Cloud confirmed not using purchased lists is still part of user contracts, and discovery is a one-strike offense.

Expert from Email Geeks explains that cleaning a purchased list doesn't make it a good list. Some validation platforms and ESPs will not knowingly accept them.

Documentation from MailerCheck explains that purchased lists can be full of outdated or invalid addresses. Most ESPs don't allow sending to purchased email lists.

Documentation from Kickbox explains that purchased lists often contain spam traps, invalid email addresses, and recipients who never opted-in. This can significantly damage sender reputation and reduce email deliverability, as ESPs and ISPs are likely to flag emails as spam. Deliverability issues arise from purchased lists.

Documentation from ZeroBounce details that a high percentage of unknowns in a purchased list can be caused by 'graymail' addresses. These addresses are technically valid but associated with users who are unengaged or have opted out, leading to poor campaign performance.

Documentation from Validity explains that "unknown" results from email validation services often arise because the receiving mail server doesn't provide a definitive answer about the validity of the address. This could be due to greylisting, temporary unavailability, or a deliberate policy to avoid revealing valid addresses to potential spammers.