Yes, Renaissance runs everything on its own infrastructure (as do most firms of that caliber, and even a tier below).

That said, many of these firms also ingest data from aggregated sources, so their research would activity be very difficult to accurately track via IP presence.

Why? The reasons for having their own datacenters are either legacy or needing some sort of specialized hardware that is not available at a cloud provider. Mana which is a new pure quant fund uses AWS extensively.

The reason for having your own computers is assured secrecy of your algorithms, and complete control over redundancy, latency and network linkages.

The reason for not having your own computers is because you can't afford them. A consideration for upstart funds, not a problem for RenTec.

If it is discovered that Amazon is stealing data from AWS customers than AWS will go out of business fairly quickly. Also even though Mana is new they do have ~$1B AUM.

> Why?

Because you don't want anyone to have access to your code and data.

If you found out that Facebook is running on AWS, wouldn't you find that strange?

Snapchat runs on Google. Dropbox ran on aws for a long time. Instagram was on aws before Facebook bought them. Netflix has basically everything but the actual video content on AWS.

AWS, Google, Microsoft, all have lots of customers. Why are those customers not strange but FB would be?

In my mind, if technology is a big part of your business then running on other people's computers only has one upside: might be cheaper. Everything else is downsides.

Therefore, A) companies that operate at a scale where the only upside disappears, and B) companies where the cloud saving outweights their expected liability cost, both will have their own datacenters. Facebook is clearly in category A, RenTech is clearly in category B. This is my understanding anyway.

Public cloud is not cheap. Public cloud is really expensive. The value of public cloud is that it's flexible (my current employer, which is massive, uses AWS in part because it has poor governance of leased data centres) and has hosted offerings that save time and operational overhead - it's quicker and easier to use SQS and DynamoDB than to host Kafka and Cassandra. Cheap it is not, however.

Some do use AWS and other cloud providers for collecting and processing data.