How to companies build millions of backlinks?

[oliverlewis]

Hi all, I use Ahrefs Backlink Checker to look at the backlinks other companies have and to see which ones I could acquire. I've noticed some companies have tens of thousands and even millions of backlinks and I also wonder how they do it.....

These companies are not large organisations and are sometimes just seo agencies with perhaps 2-3 members of staff. So my question is, where can I go to acquire leads at this level?

I appreciate organic is always the way to go and I am still going to be building my own, I just feel that I am being left behind.

Any help will be greatly appreciated.