It’s that time of year. Spring is here, and everybody needs to do a little spring cleaning, maybe get rid of some stuff in the basement. Even billionaires.

William I. Koch, better known as Bill to those who know him — and those who don’t — has decided it’s time to part with a few things below his house(s) and clean out the cellar. On Thursday, May 19, on New York’s Upper East Side at the Sotheby’s Auction House, Koch will rid himself of close to 20,000 bottles of wine from his private collection.

The three-day event is expected to bring anywhere from $10 million to $15 million for the total haul, but things have a way of going north of the wildest estimates. Koch is one of the world’s most significant collectors, and the bottles on offer include some of the most collectible and desirable wines in the world.

Beats a trip to the thrift shop to drop off stuff.

THE WINE

As would be expected from a sale of this sort, the most impressive lots (as each sale block is called) consist of wines from Bordeaux and Burgundy. According to a Sotheby’s Magazine article on the sale, a case of 1945 Chateau Mouton Rothschild, the “Victory Vintage” from the final year of World War II, one of the most perfect growing seasons on record, will be sold and is expected to collect a sale price of between $80,000 and $120,000, or around $10,000 a bottle.

Now that may seem like a lot, and there is no dispute here. But considering the scarcity of that particular wine, the fact that it is a historic bottle (its label was the first in the ongoing tradition of Chateau Mouton Rothschild bottles to feature different artists each year) and the fact that the wine may continue to age well for another, I don’t know, 20 years, maybe it’s a steal? For the right buyer, of course.

There is also a 3-liter jeroboam (four bottles) of 1959 Romanee-Conti, the epic Burgundy, and around 19,980 other bottles, including all of the First Growths; the California Cult Classics from Harlan, Bryant Family and Colgin; Italian wines from Gaja and Giacosa; Rhone Wines from Jean-Louis Chave and Guigal. You get the picture.

There’s no doubt the name Koch rings bells in an election year, but Bill Koch is not one of the famed brothers known for their contributions to conservative political causes.

Rather, he is the other brother, the one who won the America’s Cup in 1992. He is also a major industrialist and the founder and president of the Oxbow Corp., which is ranked as No. 155 on the Forbes list of America’s largest private companies.

In wine circles, Bill is perhaps as well-known for his crusade against wine fraud and forgery as he is for his personal collection. In 2009, he appeared on the cover of Wine Spectator after announcing that he had been hoodwinked by a shyster, Rudy Kurniawan, who had sold him more than $2 million of fake wines. He spent more than $25 million investigating fraudulent wine schemes.

But fear not for Bill. After the auction, he will still have somewhere in the vicinity of 23,000 more bottles left in his collection to consume in his golden years. If ever invited to dinner by Bill at one his homes in Palm Beach, Florida; Cape Cod, Massachusetts; or Aspen, be sure to bring something other than wine.

THE AUCTION

To prepare for the auction, Sotheby’s sent a team that spent six weeks in the three cellars at the Koch home getting the bottles ready for shipping.

They have produced an amazing 460-page program that not only lays out the various lots and provides detailed descriptions of the wines but also includes photos of the homes, art and America’s Cup memories.

There is a breakdown by vintage that shows the youngest bottles to be sold are a 2005 Mazis Chambertin, by Louis Jadot, and the oldest, a 1869 Mouton Rothschild. That index of wines takes 12 pages … and the type is very small.

As a special bonus to collectors in Asia, the auction guide notes that there will be free shipping to Hong Kong. For those who have paid in full, the shipments will leave the United States in June and arrive in Hong Kong in August.

Seems like a long time for a billionaire to wait for wine.

Kelly J. Hayes lives in Old Snowmass with his wife, Linda, and black Lab, Vino. He can be reached at malibukj@aol.com.