There’s been a resounding silence from Palo Alto on this and all other questions regarding Stanford’s offer to sell a large number of its assets on the secondary market — pretty much the whole portfolio, according to one source.

News of the proposed sale followed a drop in Stanford’s endowment last month of 27%, possibly the university’s largest loss ever.

“Trying to put a portfolio that huge out to market is very unusual,” the source said. “Bulk portfolios are not selling, and most sellers try to do sales quietly, to a targeted group of buyers.”

Keeping a sale this large a secret, though, is impossible — too many people know about it and will talk — so maybe Stanford is trying to avoid the stigma that was attached to Harvard last year,

Two sources confirmed to peHUB today that Cogent Partners has been hired by Stanford’s endowment to sell some portion of its private equity portfolio. Beyond that, there are still lots of questions about exactly what Stanford hopes to get out of the deal.

The news was first reported by LBO Wire. A managing director for Cogent declined to comment.

One interested purchaser with around $1 billion under management told me he contacted Cogent and was told the deal was “so big I shouldn’t even bother thinking about it.” That investor, who has purchased assets from Cogent before, said Cogent was tight-lipped about the particulars of the assets and got the impression that Cogent had a list of very large investors it was already pitching the deal to.

Another source with billions under management and who is familiar with the proposed sale said the deal is different than a traditional secondary sale because Stanford wants to work out some kind of “joint venture” arrangement in which it will continue to hold a stake in its private equity assets. For example, if it has a commitment that is 50% called down, it would rather sell 25% instead of the full 50%, the source says.

It’s not a surprise — Stanford University president John Hennessy warned in April that the university’s endowment would probably drop 30% this year due to the world economic crisis — but a 25.9% plunge in Stanford’s primary investment pool for 2008-09 is still daunting, even if the S&P 500 Index did drop a little more. (Stanford is comparing the 12 months ending June 30).

As a result, Stanford has cut the payout on individual endowment funds by 10% for this fiscal year and another 15% for next year, making everybody take a two-year hit. (“Five years of reductions would be harmful to morale, especially after the external economy recovers,” its 2010 budget plan notes. “A series of small cuts does not encourage strategic decisions.”)

The school also raised $1 billion in a bond offering last April in case of a “true emergency,” Hennessy said.