Good article. 13F reporting is important piece in understanding HFs strategy and large capital movement. As one who worked on 13F reporting system, I got oppurtunity to peek into the internals. My findings - these reportings are NOT necessarily acurate and SEC neither has infra or resources to review these reports. Secondly the threshold of 100mil is too outdated and 13F reporting needs new changes. Thirdly, these reportings are 3 months in the past - given the current age, where trading has picked up a lot, great amount of holdings get dumped out in next quarter- so 13F can be misleading - HF might has accumulated last quarter but might be selling off this quarter. So 13F reports must be read with some caveats. Hope it helps