First, it’s a professional ethics requirement. If there is the possibility of a conflict of interest in our statement, we need to disclose it to avoid misleading anyone.

In addition, there are plenty of ways to figure out where an HN member is employed besides looking at their post history. It’s not necessarily found in publicly available data, but it can be found.

Also, you have to account for future acts. Disclosing early can help insure against accusations about misconduct if you were to out yourself — or someone were to out you — later.

Company policy. This prevents headlines like "Google had employees secretly astroturf to give traction to their quantum supremacy claims" if someone decides to truly dig. I theoretically could pretend I don't work here, but I find life is easier if I just follow reasonable rules.

(I did forget to mention I didn't speak for Google, but it should be pretty obvious from context)

To disclose possible bias, in this case maybe parent feels like their opinion might be biased toward Google's claim.

I agree. Possibly to just give a bit more weight to what they say. So far, I've mostly seen this with Google employees here. Can't remember seeing anyone else mentioning this except when promoting a product.

1. Regarding policy, I think a simple disclosure like this is my personal opinion not that of my employer would be good enough. 2. Indicate possible bias: nope, one should always understand any opinion is biased due to many different reasons. So, unless this is a rigorous analysis of something, this is quite uncalled for.