-- There's been speculation that central banks are buying precious metals miners so as not to violate the Fourth Central Bank Gold Sales agreement signed by the ECB and 20 other European central banks on 19 May 2014 and lasting four years.

Money Morning: Why Central Banks Are Quietly Loading Up on Gold Shares
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The Norges Bank, the Norwegian central bank, has filed to have its Q2 2016 U.S. equity holdings be given confidential treatment. That's according to smaulgld.com.

The website reported that the NB filed their SEC form 13F for Q2, but that it includes a blank information table. It appears the "deal" that NB has struck with the SEC is to file an Amended Form 13F a year later, providing the detailed holdings.

This is particularly interesting because the June 30, 2015, filing from last year reveals the central bank held a whopping 23 gold and silver miners.

What's more, if valued at recent share prices, that portfolio was worth nearly $1 billion.
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Despite the [Swiss National Bank] ... cutting its physical gold reserves by more than half between 1999 and 2008, the central bank has been buying precious metals stocks going back to at least 2013. Their mining shares portfolio was worth $500 million at the time.

The bank reported for the period ending June 30 that it held more than 30 gold and silver miners. If you value those holdings at recent prices, the portfolio runs a cool $1 billion.