Will they lose the SEO backlinks?

Selected answers from the Dumb SEO Questions Facebook & G+ community.

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  Perry Bernard: Not a dumb question at all. Some SEO companies sell links from properties they own or control on a subscription basis. Often the business owner doesn`t realise they are not "owned" links. They are "hired" links which the current provider has created in their link farms. These are lost when the customer leaves because the provider sells that space to someone else. It`s sometimes a way to "punish" customers from leaving. "see? you should have stayed with us and your new provider tanked your SEO!". I`m not saying this is the case, but you need to investigate that further yourself to this specific situation. Track down where the links are, and if those links are built into properties that the current provider owns or has control of it could be an issue. If they are truly 3rd-party links, then it`s less likely you have to worry.
  
  Hosting change alone DOES NOT break links.Domain name changes DO break links. (repair with 301)Domain config changes CAN break links. (repair with 301)
  
  
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  Lizzy Says: Thank you Perry for your explanation!That’s what I was afraid of with what you described with “owned” links. However, the SEO company did provide my client with the list of all the backlink and login info that they shared with me. The links are 3rd-party sites like evernote.com, playbuzz.com, medium.com & livejournal.com. Nothing seems private to me. So I’m thinking from what you mentioned that might not be the case of them taking the links with them. I’ll follow up with my client to see what kind of agreement they had with the SEO company. Thanks again for your help!
  
  
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  Perry Bernard: Lizzy Says I suspect the value of those links is very low if not zero if they are comment-spam. Not saying they are, but IF they are.
  
  
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  Lizzy Says: Perry Bernard What do you mean by comment-spam?
  
  
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  Perry Bernard: Lizzy Says it`s when the link builder finds an article to comment on, adds a comment with a link to the client`s website, when the comment is made for the sole purpose of getting a link into the page. Usually, links like that are nofollow, and they are just blatant spam. They do however appear in Google`s link report in GSC. They build no value whatsoever.
  
  Like I said, I`m not saying this is the case.
  
  
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  Lizzy Says: Good to know! Thank you Perry for explaining this.