If you've come across rest-u021.immedia-semi.com, you're probably looking at a backend API for Blink, the home security camera brand owned by Amazon. The page identifies itself as a REST API, and the technical setup backs that up. It runs on AWS CloudFront, uses modern encryption, and loads quickly. There are no signs of malware or blacklisting.
What you won't find here is a company About page, contact details, or a privacy policy. That's normal for an API endpoint that isn't designed to sell to consumers or collect personal data. The domain is a subdomain of immedia-semi.com, which is the company behind Blink, but the lack of a public WHOIS record for this specific subdomain means you can't easily confirm ownership through a third-party lookup.
For developers integrating with Blink, this endpoint is likely the real deal. There's no reason to suspect it's fake based on the data. If you're a consumer, you wouldn't normally interact with this URL directly. The bottom line: rest-u021.immedia-semi.com is probably safe, but treat it as an untrusted source if you ever see it in a link you weren't expecting — always verify the domain of any API you're connecting to.