if companies could get their shareholder information from the SEC or DTCC these questions would simply not exist. Why is this information not available even under FIA? These are surely not state security issues, so the whole secrecy thing is suspect and one of the things we may hopefully see changed as things get aired out here.
This is one of those difficult situations where two conflicting public goods have to be reconciled. On one hand, there are suspicions about the markets which you and others harbor. It would be good to address those. On the other hand, there are privacy issues. While no one cares about CMKX, a precedent here could be devastating elsewhere. If one could get all trading history from FOIA petitions, then it would be possible to reverse-engineer the algorithms of a firm like Renaissance. Unlike CMKX, which is peanuts, the trade secrets of quant funds are their chief asset and are worth fortunes. Exposing those secrets and rendering them worthless would be like eminent domain without the payment. Likewise, firms like Berkshire Hathaway would not be able to accumulate positions without immediate run-ups in the price as people became aware of what they were doing.
I don't have the answer here, but I do know that it is not as simple as it looks.
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