Years ago they were already scratching their heads how platinum was able to do it consistently.
Everyone knew that their revenue wasn't from the normal markets. That's why it's not such a head scratcher that they made "private off market investments" that were wildly successful.
If they were seeing these returns from the markets, they would be Warren Buffett *10. - but they ain't nothing close. And yes, the feds/sec would be all over them ASAP.