Remember that AWS takes from developers, but doesn't give back anywhere near what they have made from the communities work.
Rather than supporting Elastic... they decide to make a hostile fork. AWS are a bunch of jerks.
(I am, as it happens, rather opposed to Amazon as a company. I canceled my Prime membership; I try to shop anywhere else if possible; I celebrated the loss of NYC HQ2. But in this case, I think they're in the right.)
Of course a lobby group like this should be transparent. But I don't expect a group like that with closed mailing lists to actually be Open.
The total budget of the OSI is in the couple hundred thousand range, i.e., comparable to a single full-time software engineer. So the fact that a few companies are each giving five-digit donations that add up to a six-digit budget doesn't seem like it's a huge priority for any of these companies. Take a look at the sponsorship levels on https://opensource.org/sponsors .
In any case, I agree that the Open Source Initiative should be transparent, and my individual membership in the OSI is not an endorsement of everything the OSI does any more than having a PyCon ticket is endorsement of everything the Python Software Foundation or their corporate sponsors do. (One specific thing they haven't done is post form 990s more recently than 2016, and I do intend to ask them to post these. But if you look at the 2016 one https://opensource.org/files/2016990EZ.pdf you can see that these aren't vast sums of money, and Craigslist donated more money to the OSI than any cloud provider.)
Edit: well, there's Microsoft's "Shared Source", but that's read-only if they like you, not particularly useful.
For a "bunch of jerks" they sure do a lot of open source stuff.
Right near the top of their list (in your link) they brag about contributing to Linux. Let's see how well their brag stacks up? Looking at the contribution reports on Linux, are AWS in the top 10?
AWS are not even on the list. https://twitter.com/ibrahimatlinux/status/768631239683158016...