The ConocoPhillips Mystery

I have two investments in common with Berkshire Hathaway; Glaxo and ConocoPhillips. As noted in my blog on 29th January 2008 ConocoPhillips was my first US investment and since then has performed well. But I was a little concerned when I read that Berkshire might have sold out of Conoco in the second quarter of this year since no holdings were disclosed in the 13F return to the SEC as at 30th June 2008. But on further examination the following statement appears in that 13F for Berkshire Hathaway which was filed 14th August 2008:

"Confidential information has been omitted from the Form 13F and filed separately with the Commission. Included in the confidential filing is information regarding Berkshire Hathaway's position in ConocoPhillips. At March 31, 2008, shares held in ConocoPhillips were included in Berkshire Hathaway's public Form 13F".

So it wasn't that there were no holdings in Conoco, rather than the holding hasn't been disclosed. Why might that be? From time to time Buffett gets a special dispensation to avoid public disclosures where this might be price sensitive leading to "copy cat" investing. But it wouldn't make sense to avoid disclosure where the stock had already been sold (unless the holding was in process of being sold down) so the more likely reason is that Buffett is actually buying quite heavily and intends to buy more.