I assume the poster is referring to SEC filings.
Simplistically, institutional investors report their holdings to the SEC (I believe quarterly) and anyone accumulating significant portions (usually over 5%) of a company's stock must file their actions with the Securties and Exchange Commission on a timely basis (think it's within 10 days). Therefore, if anyone is accumulating or "manipulating" a stock, you can check the SEC filings to find out who is behind the moves in a stock. On the other hand, if it's general sentiment that a company is doing better (or worse) and the stock rises (or falls), the stock is essentially being moved by the collective actions of hundred or thousands of investors, and therefore you won't find SEC filings to help determine the cause of the move.
One thing that makes me doubt the whole claim is that the "secret team" wasn't able to bail out Long Term Capital Management in secret. That required meetings that were quickly made public, and appeared to be quite abnormal. Yet if a PPT exists that is exactly the scenario that they would act it.
I believe that GATA has ammassed quite a bit of evidence to support the idea that a number of Reserve Banks, led by the Fed, and in conjunction with major investmant banks especially Goldman's has had a big hand in manipulating the gold market through various accounting tricks and a tricky leasing scheme.
It's just a coincidence that both Clinton and now Bush appointed former Goldman heads to be their Sec. of the Treasury. I'm sure, really.