Warren Buffett is building a large position but doesn’t want to spill the beans just yet.

It appears the famed investor secured permission from regulators to not disclose his ongoing purchase in Berkshire Hathaway’s 13F filing for the third quarter, which was published on Monday.

“Confidential information has been omitted from the public Form 13F report and filed separately with the US Securities and Exchange Commission,” the filing reads.

The Berkshire chief probably wants more time to grow his nascent stake. Revealing it might spur other investors to buy the same stock, driving up the price that Buffett has to pay.

“He is undoubtedly building a large position now and may reveal it in his next 13F,” David Kass, a finance professor at the University of Maryland who has closely followed Buffett for more than 30 years, told.
“Buffett has received confidentiality treatment several times in the past,” Kass continued. “I believe most recently around 2015 he was building a position in Phillips 66.”

Indeed, the confidentiality clause appears in Berkshire’s 13F for the second quarter of 2015, published in August of that year. Buffett and his team disclosed a $2.5 billion stake in Phillips 66 in an amended 13F filing a few weeks later.

Buffett and his team may be repeating that strategy.
“I suspect that Berkshire is building a large position in a public company and they would like to continue to do that before disclosing it,” James Shanahan, an Edward Jones analyst who covers Berkshire, told.

Berkshire’s third-quarter earnings pegged the value of its equity portfolio on September 30 at $245 billion excluding Kraft Heinz, Shanahan pointed out. However, its 13F filing showed only $220 billion in holdings.

The company’s roughly $6 billion investment in five Japanese trading houses over the 12 months to August only partly accounts for that difference in value, he added. The covert investment might be the missing link.