Legal Question

I just received a e-mail stating that a company has “used crowdsourced data such as OSM where the digital representations could be verified though comparison with hard copy or other “authoritative” sources.” for administrative boundaries.

They DO NOT mention the use of OSM anywhere on their website or in any metadata. Is there anything we can do to have them mention the use of OSM, or to have them distribute the result only under the same licence?

You could start by sending them a polite email asking them to include the correct copyright notice. I have done that a couple of them, and each time the company reacted quickly and started including the copyright. I typically said that I am happy/proud that they use our data, before asking to change the website/publication with the next deployment/revision.

On the other hand I have heard several stories where such mails were ignored.

But you could give it a try.