Sergio Sismondo, 1943-2023

By Linn’s Staff

Sergio Sismondo, an esteemed postal historian and philatelic dealer whose encyclopedic knowledge of classic-era stamps and postal history enriched collectors from around the world, died March 13 in Syracuse, N.Y., at the age of 80.

Mr. Sismondo was born in Italy and during the course of his life became fluent in five languages: Italian, French, Portuguese, Spanish and English.

Mr. Sismondo, widely regarded as an expertizer, stamp dealer and author, was profiled in Linn’s Most Influential Philatelists and Their Epic Stamp Stories, published in 2022.

As a young boy, Mr. Sismondo was heavily influenced by Victor Kneitschel, whom he called South America’s most famous and respected philatelist.

Kneitschel “had repeatedly told me that each stamp contained secret messages, each stamp was an enigma, and it was for me to discover,” Mr. Sismondo recounted in a brief autobiography he provided for the Influential Philatelists issue.

“He quizzed me regarding the [Dragon stamps of Japan],” Mr. Sismondo said.

“What had I learned about them since I got them? Who made the design? What did it represent? How was it printed? What paper was used? And so forth.

“It was a real classroom experience. Week after week I learned more about the enigma and hidden messages in each of my stamps.”

That attention to detail stayed with Mr. Sismondo for the rest of his life and was readily evident in the detailed, meticulous expertizing certificates he prepared for his clients.

Mr. Sismondo handled some of the world’s greatest rarities, including the Sweden 1855 Treskilling Yellow error of color (only one known to exist); the Great Britain 1865 Penny Red plate 77 group of three on cover sent by author Victor Hugo from Guernsey to his publisher in Paris; and a used example of the first stamp of Mauritius, which has been in collections since 1864.

His 2012 certificate for the Hugo cover is 10 pages long.

“My business model was derived from observation of the expertization processes in Italy, Switzerland, and Spain, countries where most philatelic experts work alone, from home, through the mails, with only occasional interaction with national or regional organizations, if at all,” Mr. Sismondo said.

Using a systematic approach, Mr. Sismondo began issuing certificates in 1998. He offered a detailed price schedule and frequently advertised in major philatelic publications in the United States.

“At first I thought the demand would grow very slowly, and I was prepared for a long and patient growing stage,” he said. “But it was not to be so; the demand was obvious and strong from the start.”

In the years following, demand for Mr. Sismondo’s certificates never waned. In fact, he considered backlogs in processing them a type of security because it meant he would remain busy.

Mr. Sismondo was instrumental in the genesis of the Scott Classic Specialized Catalogue of Stamps and Covers 1840-1940. The 1995 first edition was published in late 1994. The 29th edition debuted in December 2022.

The idea of a catalog devoted to the classic era of philately was first broached during a dinner in New York City that Mr. Sismondo had with Stuart J. Morrissey, then publisher of the Scott catalogs.

Mr. Sismondo signed on as a contributor to the Scott Classic Specialized catalog, working with catalog editor Jim Kloetzel. For the better part of three decades, Kloetzel and Mr. Sismondo greatly expanded the listings and transformed the Scott Classic Specialized catalog into the best single-volume resource for worldwide classic stamps.

In addition to tracking Scott catalog values for thousands of stamps, Mr. Sismondo was a prolific writer, carrying on a family tradition that has spanned more than 200 years.

During the past five years, he published 60 articles in Linn’s on the subject of postal reform, discussing relevant events in approximately 50 countries.

Mr. Sismondo was almost always accompanied by his wife and business partner, Liane. Deftly mixing advice and expertise, he gently brought his influence to the hobby for decades. He will long be remembered for his quiet, direct professionalism.

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