I have a company website for our Internet agency for over 5 years. It holds blog posts, content pages, and our portfolio mainly.
One of our biggest competitors, with mainly the same company activities as we have, went bankrupt because it lost 2 of its biggest clients. I bought their domain from the curator, and it's now ours. I don't have their old website.
The domain has a lot of relevant incoming links, and a high domain authority. Besides that I can see that it also still has a lot of traffic from people that know the old company and look to render its services.
I changed the DNS so it's the same as my website, so:
www.example.com/portfolio.html
= www.competitors-example.com/portfolio.html
And I check incoming links to the new domain and redirect them to relevant pages on my site.
But is this right? Or should I redirect it to my domain so the address bar says: www.example.com?
In short: How do I use the domain so it doesn't hurt but helps my website's SEO?